GNX5 calipers are the product of Wilwood's in-house FEA design and 3-D modeling technology. With its unyielding strength and superior piston design, the GNX5 generates positive pedal response and high clamping efficiency with a substantial weight savings over comparable OE Calipers. Base model calipers feature a natural aluminum finish protected by a durable clear coat anodizing. Forged billet aluminum bodies, stainless steel pistons, and high-temperature seals put an end to the rust, bore pitting, and seal failures that plague many OE caliper design. GNX5 caliper assemblies are designed use with DOT 3, 4 or 5.1 fluids and should not be used with Dot 5 fluids.