Flex Belt in Pakistan, Electric Muscle Stimulator, Help Men & Women Tone, Tighten, Firm, Strengthen & Flatten Abs, @DarazPakistan.Pk. Flex Belt Is An Electric Muscle Trigger (EMS Gadget) For Preparing The Muscular Strength. It Folds Over The Midriff And Has 3 Pre-Situated Clinical Grade Gel Cushions (Otherwise Called Terminals) Within.