Our Premium Shimano 110/5(bolt pattern) oval chainrings are designed for pre 2014 cranks like Shimano Dura-Ace FC7900, FC7800, Ultegra FC6750, Shimano 105 -5750 and many more with 5 bolt fitting. These are finest shift-able oval chainrings on the market. Size (Mass +/-1g): - 34T (30g) - 36T (36g) - 50T (122g) - 52T (135g) Compatibility - Shimano Dura-Ace 7900,7950,7800, Ultegra 6750, Shimano 105- 5700, Tiagra 4650, FSA, S-works and many more older cranks. Also fits Sram Force and Red but NOT compatible with Sram cranks that have 1 hidden chainring bolt (Force22, Red22). Material - CNC machined 7075 Txxx Aluminium. Long-lasting construction Finish - Type II anodizing 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.