My son really likes this piece as he can open it very quickly, no fuss, no hassle to go from jeans to pajama bottoms after school. Medium fits him, he is 5 feet 9 inches tall and weighs about 145 pounds. There is plenty of room on the belt and I haven't seen any wear since I've worn it for about a month. And like any teenager, he's picky about clothes. .Although it opens quickly, it requires effort and pressure from both sides to open it, so it is unlikely to open on its own. My husband and son tried to "accidentally" open it, and failed. I think this belt will last a while, which is amazing considering its low price and convenience. Belts in big stores are a bit cheaper, but tear easily. The texture of this belt is woven and coated, so I doubt we'll see any wear and tear any time soon. Very happy with this purchase. I am planning to buy another pair especially for my dad. This would be great for older people with arthritis.