The other end is screwed into the pump..

Back in the 80s WTB changed the handle on a Zefal soliblock pumps
so rather than fit between 2 clips on the outside of the frame.

the pump fit inside the oversized seat post tube, so It would not fall off on single track rides

Plunger is a tube, so the hose fit inside..

(only check valve is in the valve stem so pump has to overcome the valve core spring , on schrader valve stems )






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