The Walkers Silencer Bluetooth comes with the FREE Walkers App to control the program settings, monitor battery levels, adjust volume and change auto shut off time from mobile device. ADVANCED DIGITAL CIRCUIT PERFORMANCE DIGITAL BLUETOOTH RECHARGEABLE FOUR PROGRAM SETTINGSDYNAMIC WIND NOISE REDUCTION 1 NOISE FILTERING (VOICE CLARITY) 2- GENERAL 2 HI FREQUENCY BOOST 4- POWER BOOST VARIABLE GUNSHOT SUPPRESSION AUTO SHUT OFF VOICE PROMPTS USB CHARGING DOCK WITH INTEGRATED LITHIUM BATTERY USB CABLE INCLUDED INCLUDES 3 SIZES OF SURE-LOCK SIZING FINS AND 3 SIZES OF FOAM TIPS NRR 26 AVERAGE BATTERY LIFE: 14 HOURS (4 HOURS WHEN BT STREAMING)