DT Swiss RR 521 DB SBWT Presta-drilled Disc Brake Rim The RR 521 is designed specifically for wider 28-35c road tyres, featuring a 20 mm internal width that makes it an ideal match for modern endurance road disc brake bikes. Stiff and Durable Construction With a 32 mm deep semi-aero section, the RR 521 is exceptionally stiff and strong, suitable for heavier riders or those carrying extra load. Strength Boost Welding Technology creates a perfectly welded join for maximum durability and reliability. Tyre Compatibility The rim can be used with standard clincher tyres or set up for road tubeless with DT Swiss tubeless tape and valves, offering versatility for different riding preferences. Complete Build Package The RR 521 comes with DT Swiss Squorx ProHead nipples and PHR washers to complete your build. PHR washers and convex Squorx nipples align naturally with the spokes, enhancing stiffness and durability without adding weight compared with traditional eyeleted rims. Durable Finish A specialised process for the black coating produces a tough, long-lasting finish to protect the rim and maintain its aesthetic appeal.