Thanks for your feedback! I'm sorry to hear you're having trouble with the heavy leather. The standard advertised thickness is accurate ~3-3.5mm, and I find this to be the best balance of strength and comfort. In our experience, this works well for the vast majority of mandolins we've tested, but every instrument is different - buyers are encouraged to take a measurement first. If you find that it's going to be a little too thick, send along a special note at checkout. These straps are made-to-order, and we'd be happy to send you one that's a little thinner.