Usage Tips:product Name: Crane pulley block; main material: 304 stainless steel Weight: 435G; sheave size: 15 x 10mm/0.59x 0.4 inch(D*t) Sheave quantity: Singe sheave; overall size: 62 x 21 x 16mm/2.4x 0.83 x 0.63 inch(L*w*t) Main Color: Silver tone; for rope Dia.: 6mm/0.24 inch Swivel eye inner size: 14 x 11mm/0.55 x 0.43 inch (L* w ); swivel eye thickness: 4mm/0.16 inch A crane pulley block is a kind of hoisting tool, also called a Sheave, is a mechanism composed of a wheel on an axle or shaft that may have a groove between two flanges around its circumference. A rope, cable, belt, or chain usually runs over the wheel and inside the groove, if present. Pulleys are used to change the direction of an applied force, mit rotational motion, or realize a mechanical advantage in either a linear or rotational system of motion.Designed for use with rope or cord in indoor and outdoor applications, but only pulley here, rope is not included. Package Content: 10Pcs x Crane pulley block Only the above package content, other products are not included. Note: Light shooting 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.