Function: Different resistance levels to adapt to progressive strength training level, exercise arm leg muscles Specification:Material: 100% latex MPNAttribute: Yellow Belt - Ultralight (10 LBS)Green Belt - Light (15 LBS)Red belt - medium (20 LBS)Blue Ribbon - Heavy Duty (25 LBS)Black Belt - Overweight (30 lbs) Packing list:2x handle; 2x foot ring; 1x door buckle; 1x tote bag; 5x pull roper