Our Premium Sram compatible Oval chainrings (110/5bcd) are designed specifically for Sram cranks that have 1 hidden chainring bolt behind the crank arm like Sram Red, Red eTap, Red22, Force1, Force22, Rival, Rival1 and more. These are finest shift-able oval chainrings on the market.Both, inner and outer oval chainrings are optimized with smooth shifting in mind. This is why the back of the Absolute Black Oval road chainring does not feature cutouts, like other oval products on the market. Instead, we design smooth angled surfaces, to help chain to slide quickly and precisely between chainrings. Absolute Black outer oval chainrings have 6 up-shifting ramps, for easy and quick gear change, even under load. Each outer chainring also features 12 down-shifting points. Instead of steel shifting pins we use a CNC machined ramp and recess solution. Special raised ramps work in conjunction with the tooth recesses to stabilize the chain when shifting. Our oval chainrings DO NOT require any modification to the (standard) front dŽrailleur in order to work properly.Size (Weight):34T (31g)36T (36g)50T (119g)52T (131g)Compatibility:ÊONLY for Sram cranks that have 1 hidden chainring bolt behind the crank arm: Sram Red, Red eTap, Red22, Force1, Force22, Rival, Rival1. Compatible with Quarq. For Apex cranks - please navigate to our standard 110/5 rings.Material: CNCÊmachined 7075 Txxx Aluminum. Long-lasting constructionMounting: 110 BCD x 5Bolts:ÊReuse original Sram bolts except the hidden bolt. AB Outer chainring comes with the hidden bolt in the package.ÊIf changing inner chainring only - reuse all original bolts.Ovality: Optimized to each size separately. 34T- 6.5% ; 36T- 11.4%, 50/52 - 10.3% ; Timing of 108 -109.5¡ after TDC (top dead center) - Ideal for road climbing. Patent Pending.Advantages of Absolute Black Oval chainrings:One of a kind special oval shape that helps you climb easier and faster (Patent Pending)Over 15% stiffer than Rotor Qrings due to thicker, 5mm constructionBespoke AbsoluteBlack 6 point ramp and recess shifting design shifts better than any other brand and model of oval chainringYou will not feel the oval shape while pedalingYour pedaling action will feel smootherHelps reduce stress on knees and helping your legs remain fresher for longerYou will be able to maintain better cadence while climbingReduces possibility of leg crampsYou will reduce chainring/cog shifts by at least 15%