Men's Classic Chap With Jean Pockets Fully Lined W/Soft Mesh Lining covered Zippers With Three Snap Button genuine Ykk Zippers. The most important measurement is your thigh. Chaps should fit snug but not tight over your jeans. You should be able to stick two fingers down the top of the leg with no problem. The waist and length are adjustable. The waist on our chap is adjustable with lacing on the back and belt on the front. You can tie them so the two halves overlap or spread apart to get about 6 inches of adjustment. Also, the top is a belt so you can pull it tighter or leave it looser just like any other belt. Measuring Your Thigh With your jeans on measure around the thickest part of your thigh while sitting. Measuring Your Waist Your waist measurement is typically your jean's waist size with 2 inches added. This provides enough room for your chaps to fit over your jeans and possibly a belt. Measuring Your Outseam With your riding boots on measure from the top of your belt to the floor along the outside of your leg. Measuring Your Inseam While standing in relax position measure the total length of the inside of your leg from crotch to ankle.