Attwood Low Perm Primer Bulb. Ready your engine for top performance with this Low Perm Primer Bulb from Attwood: Multi-layer design prevents over-pressure bursting and vacuum collapse preventing proper fuel flow; Low-permeation bulb prevents fuel evaporation; Double-check valves allow for quick priming; Stainless steel clamps for firm seating. Order yours today! Attwood Low Perm Primer Bulb