Zefal in the past has helped with replacement caps for my kid size water bottles and had directed me to the right washers in the past. Most recently to a new presta chuck design and corresponding washers.
But given that my old Husky is indeed an SKS Rennkompressor rebrand, I'm looking into a replacement hose so that I can have thumb lock on both presta and Schrader for the rest of its life. Figuring that thumb lock should reduce push on/pull off wear on the washers.
Never thought to check the washer on the Schrader head. I don't know if it would explain why I continue to have issues with a relatively new presta chuck and washers.
Thanks
Richbiker and others for this thread, saving my old Husky/RK. Was about to plunk down $35 on a replacement pump.