74mm OD "50mm" Balboa Gecko Spa Heater Gasket O-Ring Seal - Pair

"50mm" (74mm Outside Diameter) Balboa / Gecko ribbed heater o-ring gasket seals (comes in pair) to fit all Balboa M7 & non-M7 Heaters and many others including Gecko, AEware, Hydroquip, Aquatemp, RMF, and others.  May be black, white, or clear material. Should be replaced every few years, or when there has been a chemical balance problem. 

Measurements:

• Outside diameter: 74mm
• Inside diameter: 53mm
• Total Thickness: 6mm
• Square edged O-ring side - diameter of raised ring centre to centre: 63mm 

May Have Part Numbers:

• 711-4031, 21619, B-21619, RGASHEA50M

Used in:

• Gecko Microspa, SSPA, MSPA and others
• Balboa GS, GL, EL, BP, Dominator and many others

Oring, o ring

Balboa Heater Gasket - 50mm