Plain aluminum case finish. JIMS 6-speed overdrive Softail transmission comes with a JIMS case and JIMS gears. Gear ratio''s are same as stock transmission; apart from 1st. and 6th. First gear is a longer close ratio 2.94:1 (stock is 3.21:1) and 6th. is 0.86:1 overdrive (stock is 1:1). The overdrive reduces RPM by almost 500 RPM''s compared to stock when shifting to into 6th gear. This will make higher highway cruising speeds possible with reduced engine wear; vibrations and fuel consumption. All JIMS 6-speed clean-cut gears are standard width (unlike some manufacturers that use narrower gears) for maximum strength. Completely made on CNC machine centers from forged 8620 steel and heat treated to the highest gear manufacturers specifications for uncompromised quality. All gears are dimensionally and surface finish checked for to insure quiet and smooth shifting action. Fits Softail and many custom applications. Note: Can be used in any 5-speed Softail; FXR when used with late style starter motor; primary; clutch etc.