The zefal hpx pump the zefal hpx pump incorporates the same zefal know how that goes into all their products it39s won an award from cycling plus for being 39the best on test39 it uses the 39z hpx system39 which means that the spring locking system fits any frame without the need for straps or secondary fixings zefal hpx pump features pressure 12 bar 174 psi barrel aluminium handle aluminium connection reversible presta schrader