Barakac weyn, socod deggan, qaab-dhismeed yar, iyo raad yar. Naqshadeeda wareegga xawaaraha sare leh waxay ka dhigaysaa mid ka yar oo ka fudud kombaresarada hawada ee barokaca wanaagsan ee nooca piston-ka si ay u helaan barokac isku mid ah, taasoo badbaadinaysa booska rakibidda.