DURABLE MATERIAL: sit Up Assistant Bar is made of good quality Polyester and metal, the high density sponge on the bar is comfortable to use, and Polyester webbing is wear resistant and durable . LIGHTWEIGHT PORTABLE: exercise bar is lightweight and portable, which is easy and convenient to carry and store, suitable for home and travel . COMFORTABLE TO USE: The sponge pads on the bar are very soft, give you a comfortable experience, and will not hurt your feet when exercising . MULTI PURPOSE USE: suitable for doing support lateral stretches, push ups, sit ups, bends, and flat support, this will help build body, good equipment for sports lovers . ADJUSTABLE: The strap length is adjustable, , there are multiple ways to use it for most types of beds and doors or anywhere else fit . Specification: Material: Metal, Polyester Color: Black Size Chart: 36cmx29cm/14.17inchx11.42inch Package Includes: 1 Hamstring Strap