Frequently asked questions.

Lull is a clinical-grade ear-clip system that activates the parasympathetic nervous system through the auricular branch of the vagus nerve. The technique is called transcutaneous auricular vagus nerve stimulation — or taVNS for short.

It is the most-studied non-invasive vagal stimulation form factor in the peer-reviewed literature. You wear the ear-clip for twenty minutes. The session ends on its own. No app. No subscription. No daily ritual to maintain.

A small ear-clip electrode sits on the cymba conchae — the inner upper ridge of your outer ear — where the auricular branch of the vagus nerve reaches the skin's surface. Gentle electrical pulses activate that branch.

The signal travels via the vagal afferent network to the brainstem, then projects to the brain regions that regulate stress, emotional reactivity, sleep, and autonomic balance. This is direct nervous-system input. It doesn't require you to think about it.

A soft tingle at the contact point. Comfortable, present, never sharp. You can adjust the intensity at any time during the session to find the level that feels right.

The sensation is similar to a very low-level vibration. Most people describe it as oddly calming once they get used to it. If at any point it feels uncomfortable, lower the intensity.

First session: most people feel a calming effect — slower heart rate, easier breathing, less mental clutter.

Week two: compounding benefits typically appear — faster sleep onset, reduced reactivity, faster recovery, calmer baseline.

If you haven't noticed any change after three weeks of nightly use, contact us. The 60-night home trial covers a full refund.

Apps, supplements, and breathwork all work around the nervous system. They prompt the conscious mind to slow down and hope the body follows. They require willpower, consistency, and a working baseline.

Lull works directly on the nervous system. Electrical stimulation of the vagal pathway bypasses the conscious mind entirely. You don't have to remember to breathe slowly. You don't have to be in the right headspace. The signal does the work.

For people whose stress baseline has plateaued the willpower-based interventions, this is the meaningful difference.

taVNS is a peer-reviewed technique with substantial clinical literature. Published trials in JAMA Network Open, Scientific Reports, Brain Stimulation, and Frontiers in Human Neuroscience have documented effects on sleep, anxiety markers, autonomic balance, inflammation, and recovery.

The vagal stimulation category includes FDA-approved devices for related conditions: epilepsy (1997), treatment-resistant depression (2005), migraine (gammaCore), stroke rehabilitation (Vivistim, 2021), and rheumatoid arthritis (SetPoint, 2025).

See our Scientific evidence page for full citations.

The longest cranial nerve in the body. It runs from the brainstem down through the neck and into the chest and abdomen, regulating heart rate, digestion, immune response, and parasympathetic ("rest and digest") function. Roughly 80% of its fibers carry signals from the body to the brain, making it the body's main sensor of internal state.

When the vagus is well-toned, the body returns to baseline quickly after stress. When it's poorly toned, the parasympathetic response is sluggish — chronic stress, slow recovery, poor sleep, elevated inflammation.

The literature covers:

• Sleep onset and quality
• Stress and anxiety markers
• Heart rate variability (HRV) and autonomic balance
• Inflammatory markers (TNF-α, IL-1, IL-6)
• Recovery and fatigue regulation
• Pain perception
• Gut function and digestion
• Cognitive performance and attention
• Mood regulation
• PTSD and trauma response

Evidence strength varies by condition. We're honest about which is strong and which is emerging on our Scientific evidence page.

Honestly: maybe. The research is genuinely mixed. Some published studies show increased HRV with taVNS. Others (e.g., Wiley Psychophysiology 2025) show decreased HRV with non-invasive vagal stimulation.

We don't promise HRV improvement — the data doesn't consistently support it. The honest framing is "autonomic effects observed across multiple parameters; individual response varies."

Many of our customers do report improved HRV readings on their Oura, Whoop, or Apple Watch. We can't guarantee that for you.

Lull is a wellness device, not an FDA-cleared medical device. It is FCC compliant for the US market and CE marked for the EU.

Other taVNS form-factor devices (gammaCore, Vivistim, SetPoint) have received FDA clearance for specific conditions. Those are different products at different price points, targeting different regulatory paths.

Wellness-device classification means we can describe what taVNS targets and what the research shows, but we cannot make disease-specific therapeutic claims. See our Medical disclaimer for full details.

TENS (transcutaneous electrical nerve stimulation) is a category of electrical stimulation. taVNS is a specific application within that category, with very particular parameters and a very particular target.

The key differences: Lull's parameters (frequency, pulse width, intensity range) match the ranges used in published taVNS research. The contact point is the auricular branch of the vagus nerve specifically. A generic TENS unit applied to the ear at the wrong settings won't reliably activate the same pathway.

For the vast majority of healthy adults, yes. The published safety profile of taVNS (Scientific Reports, 2022 meta-analysis) covers thousands of trial participants with a documented mild adverse-effect profile — most commonly a mild tingle at the contact point and occasional skin irritation.

That said, Lull is not for everyone. See contraindications below.

Do not use Lull if any of the following apply:

• You have an active implanted electronic medical device (pacemaker, defibrillator, cochlear implant, deep brain stimulator)
• You have active epilepsy or a seizure disorder, without medical clearance
• You are pregnant, without medical clearance
• You have a condition that may be aggravated by electrical stimulation, without medical clearance
• You are under 18 years of age

If you have any chronic condition or are taking medication for a serious issue, consult your prescribing physician before adding Lull to your routine.

Lull does not interact pharmacologically with medications — it's an electrical stimulation device, not a drug.

That said, if you take medication for a cardiac, neurologic, or psychiatric condition, we recommend a conversation with your prescribing physician before adding Lull. They may have context about your specific situation that we don't.

Stop the session and lower the intensity. The sensation should be a soft, present tingle — not sharp, not painful.

If lowering the intensity doesn't fix it, stop the session entirely and contact us at support@rederalabs.com. We'll document the experience and respond. If you experience anything unexpected (dizziness, persistent skin irritation, or unusual symptoms), discontinue use immediately.

Not without medical clearance from your prescribing physician. The published safety literature does not cover pregnancy specifically, and we err on the side of caution.

Apply a small amount of the included conductive gel to the ear-clip pads. Position the clip on the cymba conchae — the inner upper ridge of your outer ear. Press start. Adjust the intensity until you feel a soft, comfortable tingle.

The included quick-start card has illustrations. The full session is twenty minutes; the device ends it on its own.

Once daily is the standard protocol used in most published studies. Consistent daily use is what produces the compounding effects observed in the research.

Many users do an evening session as part of their wind-down. Some add a midday session for stress recovery between high-stakes calls. Two sessions per 24 hours is the suggested maximum.

Whenever fits your day. The most common pattern is 30–60 minutes before bed, because the parasympathetic shift pairs well with the wind-down period.

Other options: morning sessions to anchor a calm baseline before a busy day. Post-meeting sessions for stress recovery. Pre-workout for HRV-adjacent benefits. The research doesn't strongly favor one time of day — consistency matters more than timing.

You can read, watch something quietly, journal, or just sit. Most users find a relaxed seated or reclining posture works best.

Avoid vigorous movement (exercise, walking outside) during a session — the clip and cable can shift, and the contact point may break. Stay relatively still.

The session is twenty minutes and ends on its own. Many users do fall asleep before the session ends — that's fine. The device powers down automatically.

We don't recommend wearing the clip overnight as standard practice. The clip is designed for active 20-minute sessions, not all-night wear.

Approximately two weeks of daily 20-minute sessions on a single charge, depending on intensity setting. Recharge via the included USB-C cable in about 2 hours.

The included gel tube lasts approximately 60 days of daily use. Refills are available through our support team — email support@rederalabs.com.

Sleep is one of the strongest evidence areas for taVNS. The 2024 JAMA Network Open randomized trial showed sustained improvements in sleep onset latency and overall sleep quality, with effects persisting at 20-week follow-up.

Most of our customers using Lull for sleep report falling asleep faster within the first two weeks of nightly use. We can't guarantee it for you specifically, but the research is more robust here than for almost any other application.

Anxiety reduction is well-documented in taVNS research, particularly for stress-reactivity and PTSD-specific anxiety. Evidence for generalized anxiety disorder specifically is more limited.

That said, the mechanism — parasympathetic activation, locus coeruleus modulation, amygdala downregulation — aligns with what we'd expect to help anxiety. We make no clinical claims, but many of our customers report meaningful reductions in baseline anxiety and reactivity over 2–4 weeks of nightly use.

There isn't dedicated taVNS research on perimenopause specifically. What we can say: many of the symptoms that worsen in perimenopause — sleep disruption, anxiety, stress reactivity, autonomic instability — are areas where the broader taVNS literature is strong.

A significant portion of our customers come to Lull from perimenopause-related sleep and anxiety issues. We can't promise specific outcomes. We can say the mechanism is reasonable.

This is an emerging application. A 2026 Frontiers in Human Neuroscience study showed taVNS effects on prefrontal cortex glutamate and motor learning. The neuroplasticity and arousal-modulation mechanisms support the use case.

Many of our knowledge-worker customers use Lull as a midday reset between high-stakes calls. Anecdotal feedback is strong; rigorous research is still developing.

The autonomic-balance and inflammation-modulation pathways align with recovery. Many of our customers who track HRV, sleep, or RHR via wearables report improvements they correlate with Lull use.

The research is emerging rather than definitive. If recovery is your primary goal, we'd say Lull is worth trying but not a substitute for fundamentals (sleep, nutrition, training load management).

60-night home trial. If Lull isn't right for you, contact us within 60 nights of delivery for a refund. The device must be returned in resaleable condition to our US fulfillment address (we provide the address on RMA approval).

See our Refund policy for full conditions.

Same form factor (ear-clip taVNS). Same target (auricular branch). Same general protocol. Nurosym is a UK-based premium brand at $699. Lull is $249 at launch.

The difference is positioning and price point, not category. Both devices use the most-studied non-invasive vagal stimulation approach.

Different form factor. Pulsetto is a neck-worn band stimulating the cervical branch of the vagus nerve. Lull is an ear-clip stimulating the auricular branch.

The auricular approach (Lull, Nurosym) is the most-studied non-invasive form factor in the peer-reviewed taVNS literature — roughly 80% of published non-invasive VNS studies use ear-clip stimulation. The cervical approach is also studied but less extensively in the consumer-relevant literature.

Pulsetto also gates features behind a subscription app. Lull does not.

Different mechanism entirely. Apollo Neuro uses vibrotactile stimulation — gentle vibrations on the skin — not electrical stimulation. It's worn on the wrist or ankle.

The vibrotactile and electrical mechanisms target different sensory pathways. Apollo's evidence base is largely company-funded research. taVNS (Lull's mechanism) has a much broader independent research base.

We're a small operator, not a venture-backed wellness startup. We don't pay for celebrity endorsements, run massive influencer campaigns, or maintain a heavy retail footprint. The savings go to the price.

The device meets the same taVNS parameter ranges and uses the same auricular form factor as premium competitors. We use the open scientific literature to inform our parameters — we don't have to fund proprietary research.

$249 for a single device at launch pricing (regular MSRP $349). Bundle pricing reduces per-device cost — see the bundler on the product page for current tiers and gift inclusions.

No subscription. No ongoing fees. One purchase covers the device for life.

• The Lull control unit
• Two ear-clip electrodes
• USB-C charging cable
• 60-day supply of conductive gel
• Linen travel case with soft padding
• Quick-start card
• Lifetime device warranty

Bundle purchases include additional bonuses (silk sleep mask, etc.). See the bundler on the product page.

US orders ship from our US fulfillment partner — not from Slovenia — so your delivery times are not affected by international freight.

The company itself, Intertil d.o.o., is based in Slovenia.

US: Free expedited shipping. Typically 7–14 business days from order to delivery.

International: Available at checkout. Typically 14–28 business days depending on destination and customs.

Yes — on our order tracking page. You'll also receive a tracking number by email when your order ships.

Yes. International shipping is available to most countries at checkout. Shipping fees and timing are calculated by destination and shown before purchase. Customs duties and import fees are the recipient's responsibility.

You may request a refund within 60 nights of delivery if Lull isn't right for you. The device must be in resaleable condition with all original accessories. Email support@rederalabs.com with your order number to start the process — we'll send you the US return address and RMA approval.

See our Refund policy for the full eligibility conditions.

Yes — lifetime device warranty for manufacturing defects. If your device develops a defect through normal use, we replace it at no cost.

The warranty does not cover misuse, accidents, water damage, or unauthorized modification. It is separate from the 60-night trial.

Report within 7 days of delivery. Email support@rederalabs.com with your order number and photo/video evidence of the damage. We replace damaged devices at no cost — the default remedy is replacement, not refund.