I love these CocoKnits Leather Handle Kits - Simply untie and remove if you need to wash your favorite bag. These are really versatile and lightweight. No sewing or hardware required. Begetable-tanned leather, with washers and cords for a reinforced attachment to your bag. 

Includes:

2 leather straps (12.5" x .78")
4 leather washers (1" x .78")
4 leather cords (.08" x 5")