... standard 2. OEM production with good quality, reasonable price 3. No noise, high efficiency NOVO's timing pulley:1 ... . Plain bore: MXL, XL, L, H; T2.5, T5, T10; AT5, AT10; HTD 3M, 5M, 8M, 14M.2 ... bore: XL, L, H, XH; HTD 5M, 8M,14M.3. Material: Aluminium, Cast Iron, Steel.4. Surface Treatment: ... and most competitive in European market 2.Material:Plastic 3.Belt pulley, non-standard or standard ,OEM ...