This listing is for a brand NEW Sram RED AXS 50T Aero 1x Quarq power meter. This is the D1 version and uses the 8 bolt interface that are on most Sram road and gravel crank arms. Retail was $880, get it for less here. This is new old stock we are selling to make room for new stock in the store. We are a full service bike shop so you will qualify for warranty if needed, shop receipt will be included. Please check the pictures and ask any questions you may have prior to purchasing the rings. We also have a bunch or Red and Force crank arms in stock if you would prefer a complete crankset, new and old designs. Quarq has long been the most reliable tool for measuring power output and they have some of the best customer service. This power meter will be boxed carefully and shipped promptly with insurance for the final value amount. tracking information will be provided as soon as it is available. Listing is for USA only unless you use the eBay international shipping program. Please see our other listings for more awesome cycling accessories. Thanks and good luck.