Pearl chain: each set includes coupling, fastener, pearl chain (total 2m long), and screws, designed to assist with curtain operation. Compatible with 25 mm diameter pipe: the accessory kit is standard for roller blinds with a 1-inch (25 mm) diameter tube. Please verify the inner diameter of your roller blind tube before purchasing. Easy to install in just a few minutes: drill holes into the ceiling or wall, attach the bracket, and mount the system on top, side, or front, and on the left or right side as needed. Main materials: POM + reinforced stainless steel core; features high hardness, high stiffness, and high wear resistance. Roller blind repair kit: includes mounting bracket for external or indoor roller blind crank mechanisms, suitable for use in offices, homes, hotels, and other locations requiring roller blinds. Product dimensions: 12 x 10 x 4 cm. Color: White. Package includes: 1 x Curtain control head