These are a set of 4 resistance bands. I appreciate being able to buy these as a bundle because that is easier than buying individually since different exercises require different levels of resistance. These are 41 inch resistance bands which can also be used as pull up assists (individually or combined depending on your fitness level). They can also be used for stretching/mobility exercises or for strength training. I have used 41 inch resistance bands in the gym for various exercises and wanted them for my home gym since I am only working out at home due to Covid.This set starts at 35 pounds which means it doesn't include a truly low weight band. If you are a true exercise beginner or need a very light resistance, you may need to pick up another thinner band or look to a set that starts lighter. If you are someone who has been working out for a while, that super light band is probably way too light weight for your workouts. For me (workout 6 days a week with weight training) , the 35 pound set is just fine starting resistance.These are made of latex which can cause allergic reactions in some people.First, before you use bands, you must always check the entire band to make sure there are no signs of fatigue or damage, Trust me, a band breaking mid use can be quite painful. All bands in the set arrived in excellent condition with no signs of weakness anywhere in the band. I have tested these bands as a pull up assist and to do various strength training exercises. I have seen no issues with quality and the variety of resistance levels means I can do everything from small to large muscle groups. Good set of bands, would recommend