Made of 304 stainless steel for maximum resistance and durability. Type D is also referred to as a chain shackle, which is a narrow shackle shaped like a chain ring, usually with pins or threaded pins. D-type cockroaches are common, and most other types of cockroaches are variants of type-D cockroaches. Small loops can mainly withstand high loads. Side and shelf loading may distort or bend the D-shackle. Shackles are used to connect the sails to the sails. Product Name: Shackle Total height: 27mm Internal length: 15mm Shackle diameter: 4mm / 0.157inch Pin Dia: 4mm/0.157inch Weight: 16 grams Color: Silver Material: 304 stainless steel Package Contents: 2x Shackle Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.