Adjustable Arm Girth:
Made of adjustable velcro band, it supports a wide range of arm girth. Hole site A: From 20cm to 28cm(7.9-11inch) Hole site B: From 28mm to 40cm(11-15.7inch)
The extender is 16cm(6.3inch) in length, the armband with extender suit an arm girth max to 56cm(22inch)