Our pull-up assist band combines the advantages of conventional resistance bands and traditional assist bands in its design. This pull up resistance bands not only allows for a variety of exercises using the traditional resistance bands but also provides more assistance levels for pull-ups. In terms of user experience, the heavy duty pull up workout band is more convenient, comfortable, and safe to use than traditional assist bands. Additionally, we have designed a comfortable foot sleeve, which is the first on the market that can maintain an open shape at all times. This foot sleeve is also larger in space than any existing foot sleeves, eliminating the hassle of difficult foot sleeve wear. Moreover, a single large foot sleeve is safer than a double foot sleeve because you can let the other foot touch the ground immediately when you can't hold on. You can also easily put both feet into this naturally open large foot sleeve at the same time. Furthermore, considering the diverse usage scenarios of our customers, we have specifically designed the bands for use on indoor doorways, outdoor trees, home fitness bars, and gym fitness bars.(USA Patent)