LamiFlow GR4C unique design creates a laminar flow to reduce drag, with the air passing through the interior and exterior of the chainring, helping you to keep your momentum, while retaining the legendary stiffness of RIDEA chainrings.LamiFlow GR4C chainrings for super compact cranksets are available for double and single ring setups and it is ideal for gravel, adventure and heavy climbing road routes. The double chainrings are designed with multiple chain bridges to maximize front derailleur performance, while single chainrings use the exclusive X-ODON technology to prevent chain sucks and increase the stability of the chain.GR4C chainrings are compatible with all RIDEA GR4C cranksets, and Shimano GRX cranks.For information about weight, please refer to the documents available. P/N LamiFlow GR4C Material CNC Swiss AL 7075-T7651 BCD 110/80 mm4 bolts 2x W0T 46/30 W2T 46/30 1x X-ODON W0T 38; 40; 42 W2T 38; 40; 42