こんなの見つけたけどどういう構造なんだこれ
http://www.aliexpress.com/item/2015-Latest-Male-stainless-steel-Squeeze-version-Cock-Cage-Ring-Chastity-Art-Device-with-long-Silicone/32314415225.html?spm=2114.40010508.4.8.M3jDPl