Shop › Swinge Tube Shaft Seal Kit for Dual Shifting Cylinder Hopper Image 1 of 2 Image 2 of 2 Swinge Tube Shaft Seal Kit for Dual Shifting Cylinder Hopper $41.58 This seal kit is only for dual shifting hoppers. The seal kit includes the seals to rebuild the swing tube flange bearing. Quantity: Add To Cart Added! This seal kit is only for dual shifting hoppers. The seal kit includes the seals to rebuild the swing tube flange bearing.