This is an adjuster for extending the chinstrap when wearing a protective mask with the Type 2 Model 88 helmet. The buckle is custom-made by us and is compatible with the buckles of the official Type 2 Model 88 (or Model 18) chinstraps. The strap is made of custom-ordered polyester with the same specifications as the official chinstrap, but it is a brighter color than the official chinstrap. The length can be adjusted from approximately 9 cm to 11 cm. Normally, it can be tucked behind the rear part of the chinstrap or clipped to the helmet rubber, but to don the mask in 8 seconds, it seems you have no choice but to connect it to the chinstrap beforehand (although the chinstrap will be loose). Please research that aspect yourself. This item does not exist in official or PX (Post Exchange) products and was made at the request of personnel. Please bid only if you understand that this is a personal creation and you can correctly understand Japanese. We cannot accept claims or returns unless due to a significant error on our part.