I purchased ther these for my son after a LOT of research for a Christmas gift, so I can't speak to their long term durability YET, but I'll post an update here after he's used them a bit. My 13 year old son begged for heavy weights and resistance bands after he got to use them at a football training camp.  His doctor advised against heavy weights at his age  (can damage the bone growth and keep your smaller kid small if the growth plate hasn't fused shut yet. Anyhow, the doctor said that resistance bands can still help him bulk up like he wants WITHOUT inhibiting his growth. Yippie!!! SOOO, I started searching for made in the USA resistance bands. Trouble is, there's a catch. Resistance bands are made from rubber from a rubber tree which isn't indigenous to the US. I called and spoke to the owner (two brothers own and run this company, no pesky automated phone line or overseas language barriers to deal with when I called!). These are indeed assembled by hand by the owners in the US but because the rubber comes from Malaysia, they can't call it "Made in USA". Grin, but I can. These arrived in two days thanks to the wonders of Amazon Prime and I was VERY impressed with the density and