Cast from solid brass, this roller buckle is made to fit a strap width of 12mm (1/2")
A 'whole' buckle means that it has a bar across that holds the end of the strap down, rather than needing a separate loop of leather or metal after the buckle.
Please note that these buckles are sized across the centre bar, which holds the tongue of the buckle. They are slightly wider across the very front.
** Our latest delivery of these buckles in the 12mm size, have a lighter guage tongue than previously, so although they're still very decent buckles, we can't recommend them for use on dog collars, as their strength will be slightly compromised. ALL the bigger sizes are still as strong and reliable as ever, it is only this 12mm size that has changed.