Fieldsheer Premium Bluetooth Heated Insoles - Heated Insoles updated to include seamless Bluetooth connective via the MW Connect app, these Premium Heated Insoles provide lasting warmth and extra cushion to provide all-day comfort and relief. Durable deodorized Polyurethane fabric Up to 7 hours of warmth from a single charge Ultra-thin Heated insole for best comfort Fits in a variety of shoes and footwear Heat Zone Under the Toes 3 Selectable Heat Settings High: 150degF - Up to 2+ Hours Med: 140degF - Up to 3.5 hours Low: 115degF - Up to 7 hours Integrated 3.7volt (1) Split Micro-USB Charging Cable (1) Pair Premium Heated Insoles with Internal Battery Unisex fit Style: FSPREMBTINSOLE