MEDIROM MOTHER Labs, Inc. (Headquarters: Minato-ku, Tokyo; President & CEO: Yoshio Uekusa; hereinafter “MOTHER Labs”), developer and sales of the recharge-free smart tracker “MOTHER Bracelet”, announced that a wristband equipped with the Sauna Alert function, utilizing the device, will be introduced as the locker key for all guests at Tokyo Dome Natural Hot Spring “Spa LaQua” starting October 11, 2025.

The wristband also has a “Sauna Alert” function, which notifies users of changes in their physical condition during sauna use. This feature enables users to relax with peace of mind while bathing or enjoying the sauna.. The alert enables users to check health conditions such as heart rate at a glance which could reduce the risk of overheating or physical discomfort. Additionally, the wristband enables users to check their usage fees which further enhances convenience.

・Safe and Comfortable Sauna Experience: Health Monitoring with MOTHER Bracelet’s Two-Stage Alert System

Although the recent growht in the Suana Industry has produced more consumers seeking a comfortable sauna experience, the health risks that may arise from prolonged use has

become a growing concern. To address these issues, the recharge-free smart tracker “MOTHER Bracelet” has been equipped with a two-stage Sauna Alert function.

This feature provides step-by-step notifications based on heart rate and length of stay.

● At the first stage, the alert notifies users of the appropriate timing for a cold bath, outdoor cooling, or leaving the sauna room.

● At the second stage, the alert is triggered when the risk of dehydration or other health concerns is high, encouraging users to promptly exit the sauna and rehydrate.

The algorithm was developed under the supervision of Dr. Tadashi Yamamoto, a cardiologist, and features highly accurate notifications based on medical evidence. This enables a balance of comfort and safety, offering a new bathing experience where users to manage their health without strain.

※This feature is intended to support health management and is not intended for the diagnosis, treatment, or prevention of disease. If you have concerns about your health, please consult a physician or other healthcare professional.

・A Stress-Free Spa Experience Enabled by the MOTHER Bracelet

The original “MOTHER Bracelet” band, developed exclusively for Spa LaQua, is equipped with NFC functionality. With just the wristband, users can smoothly unlock and lock their lockers as well as make payments for food, beverages, and services throughout the facility.
In addition, users can check their usage charges at any time using tablets installed within the premises.

Looking ahead, MOTHER Labs plans to develop new systems to deliver an even more fulfilling spa experience. Upcoming features include the visualization of crowding conditions within the facility, tools to monitor levels of relaxation and recovery, and personalized services such as recommending optimal programs tailored to each user. Through these innovations, guests will be able to enjoy a more comfortable and secure bathing experience aligned with their physical condition and personal preferences.

■About the MOTHER Bracelet, Recharge-Free Smart Tracker

MOTHER Bracelet is the world's first* 24/7 recharge-free smart tracker. It uses innovative technology from a Silicon Valley tech company that allows for power generation based on temperature differences between body and surrounding air. The recharge-free feature eliminat es the risk of data loss when a device is taken off for recharge. MOTHER Bracelet records

five basic metrics: heart rate, calories burned, body surface temperature, step count, and sleep.

Official Website: https://mother-bracelet.com

◾About Tokyo Dome Natural Hot Spring Spa LaQua

Facility Information
Facility Name: Tokyo Dome Natural Hot Spring Spa LaQua
Opening Hours: 11:00 a.m. ‒ 9:00 a.m. (the following day)
Admission Fee: Adults (18 and over) ¥3,500 and up / Ages 6‒17 ¥3,200 and up
● Admission fees vary depending on the day of visit.
● Late-night surcharge (for stays between 1:00 a.m. and 6:00 a.m.): ¥2,500
● Healing Baden (ages 18 and over only): ¥1,100
● Please check the facility’s terms of use before visiting.
Closed: October 6 (Mon) ‒ October 10 (Fri), 2025
Other Closures: May occur for inspections or maintenance. URL: https://www.laqua.jp/spa/

■ABOUT MEDIROM MOTHER Labs Inc.

A subsidiary of MEDIROM Healthcare Technologies Inc. (NASDAQ: MRM), focuses on the health- tech sector. The company’s core activities include the 'Specific Health Guidance Program’ offered through the ‘Lav’ health application and development and sales of the 24/7 recharge-free MOTHER Bracelet smart tracker. By leveraging the features of the recharge-free MOTHER Bracelet, MOTHER Labs offers customizable health management solutions across diverse sectors, including caregiving, logistics, manufacturing, etc.

◼MEDIROM Healthcare Technologies Inc.

MEDIROM Healthcare Technologies Inc.
NASDAQ Symbol: MRM
Tradepia Odaiba, 2-3-1 Daiba, Minato-ku, Tokyo, Japan