These quality solid brass belt buckles are great for many strap goods. The roller buckles are great for small pet collars. The chrome plated roller buckles look great for straps used to buckle down black leather purse flaps. The light steel roller buckles work well for watch straps and wristbands. The center bar buckles function well for adjustable straps.
The 1/2 inch an 5/8 inch measurement is for the inside of the buckle. This will allow you to know how much space you have for a strap.