1. Suitable for wooden walls, tiled walls, glass walls, brick walls, cement walls, and ordinary walls. The distance between the wall and the shower curtain rod should be less than the extension length of the telescopic rod; therefore, choose the appropriate size. 3. Due to objective reasons, product dimensions and colors may vary slightly, which is normal. We promise to answer your questions within 24 hours. 4. The telescopic rod uses a spring lock that connects the inner and outer rods without screws. The rod body is made of stainless steel, with strong load-bearing capacity, not easily deformed, and durable. Product material: Stainless steel. Product color: Black/Stainless steel. Product features: No drilling required/Telescopic. Applicable scope: Various cabinet doors. Note: The shorter the inner tube, the higher the load-bearing capacity; the larger the rotation angle of the inner tube, the lower the load-bearing capacity. Working principle of the telescopic rod: The telescopic rod extends and retracts through two sliding tubes. The more sliding tubes, the greater the force generated, meaning the inner tube extends further. Please note that the extension length of the telescopic rod depends on the elasticity of the spring; therefore, the extension length may vary slightly. A deviation of 1-2 cm is allowed. Telescopic length: 50 cm - 80 cm