The Arm Blaster is the perfect tool to build and grow your biceps. It features an adjustable strap, however its a one size fits all mould - tucking nicely under the armpits to completely isolate the bicep concentration movement. This tool is ideal for those looking to build up their biceps and arms, and would be a great addition to any home or gym workout. With its easy to use design, it is perfect for all levels of fitness.