The Resistance 90 portable resistance training system is a lightweight kit that you can take anywhere. You can set this up on any door using the Spine strap, and then you can do a full workout or key in on a specific muscle group. Resistance 90 supplies you with a dual-band Slastix resistance band at your desired weight and color selection, a collapsible arm bar, and Spine Strap. The Spine Strap can be secured to your door and provides immediate access to seven possible anchor points from the top of your door to the bottom. Resistance 90 adapts Stroops' patented Slastix resistance band technology to create a product that is long-lasting, safe, and attractively designed. Slastix resistance bands are made to protect the tubing from outer abrasions that would otherwise weaken the band and hasten its breakdown. In addition, you'll be kept safe from potential breakages as the safety sleeve restricts the band from wild snapbacks. The Resistance 90 system can be used to work out every part of your body from shoulders to legs. The benefit of Resistance is it can either be taken on the go for freestyle exercise or set up with your Spine Strap for an at-home workout session. The Resistance 90 is offered with a medium 20-pound resistance.