The only EMF wearable with a published HRV study.
Week two: sleep score up 11 points. Nothing else changed. - R.K., Software Engineer
Within seconds of contact with skin, the stone absorbs body temperature. Thermal conductivity response time: approximately 3 seconds. Same property visible in the ice-melt demo.
As the stone responds to body heat, it emits sub-terahertz radiation in the 480-700 GHz range - the same range the human body naturally produces via sweat ducts (Hebrew University, 2022).
Terahertz radiation is absorbed 99% in the top 500 micrometers of skin tissue (KAIST). A localized thermal interaction of approximately 1.4 degrees C - small, consistent, continuous.
Sustained thermal stimulation at the skin surface feeds into the vagal nerve pathway - the primary highway of the parasympathetic nervous system. This is the calm-down signal the body was not receiving.
Most EMF stones make invisible promises. No published data. No physical property you can test.
The ice test. Put the pendant on ice. Watch for 10 seconds. The terahertz stone melts ice faster than any natural stone of comparable size. That is extreme thermal conductivity. You can run this test in your kitchen before reading another word.
The study. In January 2024, researchers published a peer-reviewed study testing a terahertz wearable over 14 days. Measured outcomes: RMSSD and HF power — both parasympathetic nervous system markers. Both increased significantly after 14 days.
Source: Journal of Biological Research and Environmental Sciences. Open access: jelsciences.com/articles/jbres1865.pdf. No other terahertz pendant has published this data.
No physics debate required. Five steps, all verifiable.
Within seconds of contact with skin, the stone absorbs body temperature. Thermal conductivity response time: approximately 3 seconds. Same property visible in the ice-melt demo.
As the stone responds to body heat, it emits sub-terahertz radiation in the 480-700 GHz range - the same range the human body naturally produces via sweat ducts (Hebrew University, 2022).
Terahertz radiation is absorbed 99% in the top 500 micrometers of skin tissue (KAIST). A localized thermal interaction of approximately 1.4 degrees C - small, consistent, continuous.
Sustained thermal stimulation at the skin surface feeds into the vagal nerve pathway - the primary highway of the parasympathetic nervous system. This is the calm-down signal the body was not receiving.
The 2024 JBRES study: after 14 days of continuous wear, RMSSD and HF power both increased significantly - parasympathetic markers that biohackers track as HRV. A measurable baseline shift toward recovery.
Six components, each with a specific functional role.
Not mined - manufactured in Japan using an industrial synthesis process. Natural crystals have variable structure; this stone has defined material properties batch-to-batch. Consistency is what produced the 2024 HRV study results.
Emits sub-terahertz radiation in the range the human body already produces naturally via sweat ducts (Hebrew University, 2022). The body does not experience it as foreign - resonance, not intervention.
Measurably higher thermal conductivity than any natural alternative. The ice-melt demo makes this visible in 10 seconds. Same property, two contexts: ice melt and skin interaction.
Terahertz radiation absorbed 99% in the top 500 micrometers of skin - exactly where peripheral nervous system receptors are densest. Shallow depth means safe, consistent, targeted stimulation (KAIST).
Hypoallergenic, nickel-free. Holds the stone at a slight angle to maximize skin contact surface. Engineered for 24/7 daily wear without skin irritation. Effectiveness depends on consistent skin proximity.
Adjustable 18-22 inches - chest-level placement for proximity to major circulatory vessels. Same surgical-grade stainless as the setting. No plating, no coating that wears away.
From peer-reviewed studies and documented surveys - not our marketing team.
Of people who identify as electromagnetically hypersensitive report sleep disruption as their primary symptom.
Source: Austrian population survey (Forschungszentrum Seibersdorf)
The study duration required to produce statistically significant RMSSD and HF power improvement in the 2024 JBRES peer-reviewed trial. Our 60-day guarantee gives you four times that window.
Of terahertz radiation absorbed in the top 500 micrometers of skin tissue (KAIST research). Surface-level interaction, exactly where peripheral nervous system receptors are densest.
The price range of the current category leader. No published HRV study. No demo-able physical property. Our price: $34.99-$74.99. Better mechanism. Lower price. Existing data.
Six criteria. Side by side. One of us has a published study.
Other EMF Pendants
Published peer-reviewed HRV study (JBRES 2024)
Physical property testable at home (ice demo)
Lab-synthesized material with consistent properties
Mechanism that bypasses the physics debate
Affordable daily wear
60-day money-back guarantee, no restrictions
I'm a software engineer. I think in systems. I bought this because a colleague mentioned the HRV study, and I figured I could track the effect myself - I wear an Oura ring. Week two: sleep score up 11 points. Week three: resting heart rate dropped 4 BPM. I am not claiming causality. I'm saying those numbers moved, and nothing else changed.
I've been living in an apartment in Manhattan for three years. The router is 6 feet from my bed and I can't move it - lease restriction. I've had disrupted sleep the entire time. I wore this for two days and slept through the night. That hasn't happened since I moved in.
I was most convinced by the ice test before I even wore it. The melting ring around the stone was clearly faster - you could see it in real time. Wore it for two weeks. My mornings are less foggy. Ordering a second one for my partner.
Biohacker here. Full stack - Oura, CGM, cold plunge. Added the pendant three weeks ago. HRV trend uptick visible in week two. Maybe 8 points RMSSD - consistent and in the direction of recovery. Interesting enough to keep.
I forgot I even had it until I lost it in my bag for four days. By day two I was wondering what was different. Found it on day four. Put it on. By that night I remembered what it was doing.
Bought one for me, one for my partner, one for my daughter whose sleep changed after we installed a mesh WiFi system. All three of us are sleeping better.
The product works. 4 stars because shipping took longer than stated. The stone itself: I wear it daily. Headaches are noticeably less frequent - was having them 3-4 times a week, now maybe once.
I bought this for the EMF reason. The fog in the afternoons did improve. What I didn't expect was the sleep change. I've been falling asleep faster. Haven't used melatonin in three weeks. Ordered a second one.
First adopter reviews - updated as they come in.
Try It for 60 Days - Risk Free
I want to be honest about why this product exists.
I spent two years watching people close to me struggle with sleep and chronic exhaustion they could not explain. They had dismissed every crystal pendant. They had good reason to.
What changed for me was the HRV study. When I read that a terahertz wearable produced statistically significant RMSSD improvement after 14 days, I paid attention. When I tested the ice demo and watched a stone of this size melt ice faster than anything I had put next to it before, I understood there was a physical property here that no crystal product had ever showed me.
Most people notice something in the first few nights. The 60-day guarantee exists because the study measured at 14 days, and I want you to have four times that window.
If it does not shift anything for you, I want it back. Full refund, no friction.
— Claire
Most pendants start with a dug-up stone. The problem: natural crystals have variable structure. Two pieces of shungite from the same mine can have meaningfully different carbon concentrations. When your mechanism depends on consistent thermal conductivity, natural variability is a design flaw.
The terahertz stone is manufactured — synthetic silicon, produced in Japan using an industrial synthesis process designed to yield consistent terahertz emission properties across every batch. The same specifications that produced the stone tested in the 2024 HRV study are the specifications our supplier holds.
Japan leads this material category because decades of investment in silicon synthesis for the semiconductor industry created the manufacturing tolerances that produce a consistent terahertz stone. This is a precision material.
Every stone we receive is inspected for the ice-melt characteristic — the visible indicator of thermal conductivity. If the ice demo does not produce the expected melt rate, the stone does not ship.
Two things, both verifiable. First: a published peer-reviewed study (JBRES 2024) showing measurable improvement in RMSSD and HF power after 14 days. No other EMF pendant has comparable published data. Second: a physical property you can test in 10 seconds - put it on ice, watch the melt rate. That thermal conductivity is the same property creating the skin-tissue interaction behind the study results.
No. It doesn't block signals. The mechanism is different: thermal interaction with skin tissue, which triggers a shift in how the nervous system responds to stress. The 2024 study measured that effect directly.
Around the neck as a pendant, ideally with skin contact. The thermal interaction requires proximity - direct skin contact is optimal. Most people wear it all day and remove it at night, then place it near the body on the nightstand.
RMSSD and HF power - both markers of parasympathetic nervous system activity. RMSSD is the primary HRV metric tracked by Oura, Whoop, and Garmin. Both increased significantly after 14 days. Source: JBRES 2024. Open access: jelsciences.com/articles/jbres1865.pdf
The study used a THz+tourmaline wearable. Our pendant uses a manufactured terahertz stone with the same thermal emission properties. We present the study as supporting evidence for the thermal mechanism, not as a direct product certification.
Extreme thermal conductivity - a material property of synthetic silicon. Heat transfer rate is measurably higher than quartz, shungite, tourmaline, or obsidian. The same conductivity that accelerates ice melt is what creates the rapid skin-temperature response when worn.
Yes. Terahertz radiation is non-ionizing - no risk of DNA damage or tissue injury. Same class of radiation used in hospital imaging and airport scanners. The pendant contains no electronics and does not interfere with WiFi, phones, or any other device.
Return it within 60 days for a full refund. Full stop. The guarantee exists because the study measured at 14 days - we want you to have four times that window. The risk is entirely on us.
Try it for 60 days. If nothing shifts - not sleep, not HRV, not mornings - send it back. Full refund, no questions. The study measured at 14 days. You get four times that window.
Try It for 60 Days - Risk FreeTry it for 60 days. If nothing shifts - not sleep, not HRV, not mornings - send it back. Full refund, no questions. The study measured at 14 days. You get four times that window.
Try It for 60 Days - Risk Free
