Clutch › HELIX/SPRING SHIM TSS-04 Image 1 of 1 HELIX/SPRING SHIM TSS-04 $7.95 Helps maintain peak RPM at extreme elevationsImproves backshift at high elevations and in very steep conditions Quantity: Purchase Added! Helps maintain peak RPM at extreme elevationsImproves backshift at high elevations and in very steep conditions