The Sunday Darkwave frame is built out of 100% 4310 chromoly and features Sundays signature dent-resistant wave down tube to give riders a little extra peace of mind when things dont go according to plan. It stays looking clean with refined details like an integrated seat clamp, tapered stays, and integrated chain tensioners. Removable brake hardware and gyro tabs are also available when you need them and disappear when you dont.Features-100% 4130 chromoly frame-Broc Raiford signature geometry-Removable U-brake hardware and Gyro tabs-Integrated seat clamp-Wave Down Tube: Down tube dents are common with the competitors frames and they significantly weaken the front end of your bike. The double-butted, 1.45" diameter down-tube feature Sundays proven Wave shaping to fight denting against contact made from a rail, ledge, coping and whatever else happens to get thrown at it. -Miter Cut Top Tube: A miter-cut top tube creates a precise joint with the seat stays during welding. This increases the strength substantially over frames that use a “sandwiched” top tube at this critical junction.-Tapered Chain & Seat Stays: Both chain and seat stays taper to provide a refined and clean look to the frame while still providing strength. They are both angled on the inside for improved chain clearance and weight savings. -Hollow Dropouts with Chain Tensioners: Hollow 8mm wide dropouts are as light as a solid 5mm dropout, but over twice as strong. There is a small internal chain tensioner to hold the wheel in position and to simplify wheel removal.Item Specifications-Color:Matte Dark Brown-Mfg Size:21.25-Rear Axle:14mm Threaded x 110mm-Platform:Darkwave-TT (Effective):21.25-Wheel Size:20"-Fork Type:Not Included-Frame Material:Steel-Defined Color:Brown