3mm Strong Steel Pipe Is Used. Transparent Rubber Covers On The Left And Right Sides-This Will Prevent Unnecessary Traces On The Door Frame Making This Lever Equally Suitable For Renting A House Unique Design To Ensure Safety-Specially Designed Slider When The Weight Is Increased The Slider Will Slide Down So As To Cling To The Wall. Thick 3mm Steel Pipe Durable. Manufacturered by BENGKUI. Telescopic System / Pole Diameter Sturdy Steel Construction Easy To Operate. There Are Four Specifications S: 72-92cm M: 92-124cm L: 110-138cm Xl: 130-175cm. Before Purchasing Please Measure The Installation Position And If Necessary Ask Customer Service In Time. Safe and slip resistant bid farewell to cocoons and bubbles. You can use wide narrow or parallel handles for a variety of pull-up exercises. Unlike a door stop your movement is not restricted by the door frame but provides you with a permanent and stable structure