Product Description The Wolf Tooth Components Direct Mount SRAM chainring can be used for cyclocross cranks from SRAM and is also compatible with Flattop chains. Specifications:Application:Cyclocross, Gravel, RoadMount:SRAM Direct MountTeeth:38 T, 40 T, 42 TGearing:1x9-speed, 1x10-speed, 1x11-speed, 1x12-speedTechnical Information:Offset:6 mmChainline:47 mmMaterial:aluminium (7075-T6)Compatibility:Crank: SRAM Cyclocross, Gravel and Road CranksetsPraxis Works Road-/CX-cranksalso suitable for SRAM Direct Mount GXP cranks and BB30 cranks with long axle (101.5 mm) Chain: all 9-speed, 10-speed and 11-speed chainsSRAM Flattop, SRAM Eagle, Campagnolo and KMC 12-speed chains10-speed chain recommended for 9-speed drivetrainsFeatures:Wolf Tooth Wide-Narrow designMade in the USANote from the Manufacturer:Please reuse the 3 original spider bolts to directly mount chainring or buy Wolf Tooth spare bolts (installing/removing is best done with T25 L-key). It is best to use a clutch rear derailleur. Technology:Drop-Stop® B Wolf Tooth has invested countless hours in the design, prototyping and testing of their Wide-Narrow chainrings and has developed a highly innovative tooth profile. Test riders around the world have confirmed that this design brings unparalleled performance. The right side of the chainring tooth has a different shape than the left side. The right side transmits the power to the chain and the left side opens a free space for cleaning mud and dirt. Since the two sides have completely different functions, it makes sense to design them differently, true to the motto: extra reinforcement where you need it, less material where you don't. The right side of the Drop-Stop tooth is as wide as possible to distribute the load over a larger area, which also minimises wear. The left side of the Drop-Stop tooth helps to guide the chain, but it does not transmit any load. Therefore the left side is narrower than the chain roller. Wear is not an issue on this side, so Wolf Tooth was able to save material and create a better mud clearance channel. More free space means less friction and less change of the chain being dropped due to mud. In the B version, the drop-stop profile is optimised for use on wheels with drop bars. The teeth are slightly narrower and the valleys between the teeth are deeper to accommodate the larger rollers of SRAM Flattop chains. The outer sides of the narrow and wide teeth touch the chain to guide it. Manufacturer Numbers:38 tooth:SDM38FT40 tooth:SDM40FT42 tooth:SDM42FTContents:1 x Wolf Tooth Components Direct Mount SRAM Flattop Chainring Weight: black | 40 : 106 g black | 42 : 111 g Manufacturer: Wolf Tooth Components 6400 W 105th St Bloomington MN 55438 USA info@wolftoothcomponents.com Distributor: Cosmic Sports GmbH Leyher Straße 47 90763 Fürth Germany info@cosmicsports.de