Product Description This Gates CDX front belt drive sprocket for touring and off-road use has four arms and a 104 mm bolt circle diameter. It is made of 6061 aluminium. Specifications:Application:All Mountain, City & Touring, Cross CountryTeeth:39 t, 42 t, 46 t, 50 t, 55 tMount:104 mm bolt circle diameter, 4-armTechnical Information:Width of the teeth:11 mmTooth division:11 mmMounting web thickness:3.1 mmOffset:3.1 mm (assembly surface), 1.55 mm (centre line)Inner Diameter:88 mmArm width:19 mmMaterial:aluminium (6061)Features:CDX level: high-end version for high loads and best performancesuitable for mud, sand, snow and ice as well as all roadsmiddle guide groove (CenterTrack)high mileageblack anodisedTechnology:Gates Carbon Drive System The main advantages of the Gates Carbon Drive system are cleanliness, smoothness and robustness. Urban commuters as well as mountain bikers, e-bike users or leisure riders benefit from the high mileage. Oil-stained or rusty chains are a thing of the past. Clean: No lubricant means no accumulation of grease and dirt. Smooth and silent operation: no metal-to-metal contact of the chains. Light: The whole system weighs less than a standard bicycle chain. No elongation: Belt does not need to be re-tensioned or replaced. Self-cleaning: CenterTrack and MudPort profiles are specially designed to repel mud, dirt, snow or other contaminants. Consistent efficiency: The drive boasts a long service life compared to that of a conventional chain, where efficiency is significantly reduced by wear or dirt. Installing a Gates Carbon Drive Belt Drive requires a specially-made frame, therefore we strongly advise against using one to modify a conventional framework. Models:39 tooth: Outer Diameter:134.8 mmManufacturer Number:CT11394AA 42 tooth: Outer Diameter:145.2 mmManufacturer Number:CT11424AA 46 tooth: Outer Diameter:159.3 mmManufacturer Number:CT11464AA 50 tooth: Outer Diameter:173.2 mmManufacturer Number:CT11504AA 55 tooth: Outer Diameter:190.7 mmManufacturer Number:CT11554AAContents:1 x Gates CDX 4-Arm Front Belt Drive Sprocket Manufacturer: Universal Transmissions GmbH Walkmühlenstraße 195 99974 Mühlhausen Germany shop@carbondrive.net Front sprockets from Gates are used in combination with a Gates belt (belt not included) instead of a chain. Consult the Gates Carbon Drive Bicycle Calculator to determine the correct part. Gates uses 4 types of product lines. These product lines are often used by Gates to indicate for which type of bicycles the part is intended. This product belongs to product line: CDX: powerful commuter bikes, trekking bikes, mountain bikes, cargo bikes and e-bikes, and extreme conditionsProduct line: CDXMaterial: 6061 aluminiumGates Article number: 740590 EAN code: 4262558681049 Supplier number: 78980700-AM Retail packaging: Yes