Pulley Rail Ball Wheel, 4Pcs 0840UU 8x40x20.7mmU-Groove Pulley Roller Guide Wheel for Doors and Control Mechanical Devices

• ✔ 【Excellent Material】 - These pulleys are made of high quality metal and plastic material, sturdy and wearable.
• ✔ 【High Performance】 - Internal lubrication grease, smooth operation, good mute effect. U-shape groove design, smooth reduces friction.
• ✔ 【Ideal Replacement】 - The pulley wheel widely used in doors and to track and drive mechanical equipment.
• ✔ 【Slide Flexible】 - There are total 4 pieces of pulleys in one set that you many use for many projects.
• ✔ 【Overall Size】 - Inner Diameter: 8mm / 0.3in; Outer Diameter: 39.5mm / 1.6in; Thickness: 20.1mm / 0.8in.

Description: Made of high quality material, these wheels are durable, sturdy and durable. There is grease, it is quiet running, good mute effect. U-shape groove design, smooth can reduce the friction. There are a total of 4 roles in a set that you use for many projects. It uses wide in doors and to track and control mechanical devices. Specifications: Model: 0840UU Type: U-groove Material: metal, plastic Color: Black Inner diameter: 8mm / 0.3in Outer diameter: 40mm / 1.6in Thickness: 20.7 mm / 0.8 inches Quantity: 4 pieces Weight: 109g (approx.) Package includes: 4 x rolls