adjusting roller for sliding door 1.Aluminium frame, 2.Nylon wheel, 3.Good bearing. adjusting roller 1. Aluminium frame;2. Nylon wheel;3. Real bearing We are one of leading manufacturer specialized in aluminium door and window accessories in Ningbo, Zhejiang prov.. Our mainly products are window latch, sliding lock, pulley, handles, operators, Joint corners etc...Meanwhile, most of our products ...