plug

water jacket plug / water-jacket plug

base plug

delay pellet plug

fill / plug the gap

gas plug

glow plug

igniter plug

high-explosive point detonating nose plug

gas plug and tube assembly

base plug (of ammunition)

breech plug

bridge plug

cold plug

cylinder filler plug

vent plug

evacuation plug

expansion plug snap ring

filling and drain plug

hard fiber plug

hard steel plug

hot plug

inspection plug gasket

insulator of spark plug

fouled spark plug

fuze-hole plug

constricted air gap spark plug

ignition plug

shanted surfаce discharge spark plug

spark plug body

spark plug central electrode

spark plug rate

starting spark plug