«Taidacent Smart Mattress Breathing Sleep Belt Heart Rate Respiration Sensor Espiratory Heart Rate Piezo Restive Pressure Sensors» https://www.aliexpress.com/item/1005003212843492.html?spm=a2g0o.cart.0.0.58f93c004oO6Y4&mp=1 Is this sensor belt in this sleep tracker? https://www.aliexpress.com/item/4000016737162.html?spm=a2g0s.9042311.0.0.27424c4d8PccMO The Aliexpress respiratory belt is very sensitive, the signal reminds of the signal of a Bitalino Physioplus Inductive sensor: https://plux.info/sensors/317-respiration-rip.html see also the discussion here: https://www.eevblog.com/forum/testgear/read-out-sensor-data-from-sleep-tracker-with-bluetooth-sniffer-tools/msg3471796/#msg3471796 Scott Harden, …