Seal and space kit for 5900e, 5900s, 5900-BT and 5900e Air Valves.

Also works for Models 5700 and Fleck 5600 valves. Fits CSI Sig I, CSI Sig II, and CSI Sig III control valves as well.

Includes a small packet of 100% food-grade silicone lube, no other lubricant should be used.

Does your control valve drain leak or do you see water running to drain even when not in backwash?  Replacing the seals will fix that problem in most cases. However you may also need to replace the piston as well, if it scratched or damaged from minerals or sand in the water:

Link to standard filter piston.

Link to Air Charger type piston.