ART Automotive rig crew: Does anyone know how to maintain Avenger F1000 suction cups?

[SHINOBIENDO]

One is noticeably losing more suction than the other

 

[SprayGun]

Um dont pull the buttons out to take them off. thats about it. i lost suction in one because my brother in law used tem and pulled the pump buttons out to get the cups off and ruined a seal. I guess if you lose suction you just replace an oring