If you need to workouts with different levels of your weight plates(not included),you will need threaded dumbbell handle and extension bar. Its a wonderful equipment for a variety of dumbbell exercises to strengthen muscles. Features: Foam Padded Extension Bar: Heavy-duty iron pipe and plastic cover for extension bar for durable and stable use. Soft foam cushion provides relief to neck and shoulders while training. Standard Dumbbell Handle: Built-in strong iron pipe and plastic cover.The grip handle on the bar allows your hand to grip the bar securely. Fastener Collars: Easily adjust the position of your weight plates(not included) and prevent them from easily sliding off during exercises. Convenience: Ideal for various warm ups sports and strength workouts like arms, ,shoulder, abdominal,legs or back training. 2-In-1 Design: Different combination meets your different demands. Specification: Material: Iron + Plastic + Foam Loading capacity(Dumbbell Bar): Max. 20kg/44lb (for each) Dumbbell bar length: 40 cm / 15.7 in Extension bar length: 40 cm / 15.7 in Package size: 40 * 15 * 6 cm / 15.7 * 5.9 * 2.4 in Package weight: approx. 1.5 kg / 3.3 lb Package List: 2* Handle Bar 1* Extension Bar 4* Fastener Collar