'The Theragym loop is the perfect additional appliance for Funkitonelle exercises with resistance, whether you're at home, in the gym or in the office. Thanks to its small size and low weight, it is also easy to store and to transport. Resistance: Yellow = Light Green = Medium Blue = Strong Black = Extra Strong technical data: Material: Latex Size: /2 circumference x Width Yellow = approx. "30 x cm Green = approx. x cm Blue =" approx. 28 x cm black = approx. 27 x cm * With Pain Issues Before You Started With Your exercises to your doctor or physiotherapists.