The closure is an inside lock that is removed with the key when opening. The lock is completely hidden. 2 keys are supplied. The A-ring comes in a new curve oval form. A-ring approx. 52x45mm. It adapts much better to the man's anatomy. It is a very robust model with a material thickness of 3mm. The inside diameter of the cage is 33mm. The length of approx.: 45mm below and 85mm above. The total length with A-ring approx. 85mm. The material is stainless steel. The total weight is approx.: 325 grams.