The double bearing can effectively support the high-speed rotation of the pulley and reduce the friction coefficient during its movement. Concave pulley made of stainless steel is suitable for wire ropes, and with a smooth surface aiming to minimize wear on the rope. Constructed of high quality aviation aluminum material, and it has strong strength and good toughness, and delivers outstanding stability and durability. Max load capacity is up to 25KN and suitable for 13mm diameter rope. Dimension:4 1/4'' x 3 1/4'' x 1 1/4''(11 cm x 8 cm x 3 cm) Maximum allowable speed: 25 m/s Sheave mounted on self-lubricating bushings for efficiency Attachment point accepts up to three carabiners to facilitate use. This trolley is made for running on steel cable, but can also be used on rope. Closed Strength: 5600lbs / 25KN For 5/16 - 3/8 - 7/16 or 1/2 inch Cables