Method of use: the first step: put tape on the edge of the bed the second step: the tape through the bed board inside with hooks to tape out of the can step 3: insert the strap lock on chip at the same time adjust good on the surface of the ball and bed height according to the locked excess tape add the second bar hole. 1: lose weight thin abdomen effect is good the bed in the morning and evening exercise easy to stick to it. 2: simple installation does not occupy a space city house prices high big can't afford to injury small is king. 3: good bed doing sit-ups exercise comfort is suitable for men and women old and young hotties. 4: suitable for all kinds of domestic mainstream bed. (black cloth belt is 4.5 meters long) Anytime anywhere can exercise at home. The benefits of sit-ups: can treatment of gynecopathy Can exercise the groin Can reduce the belly Can treat stomach!