Suit Carburettor With No Spacer 5/16 In Thread X 1.700 In Oal (4-Piece). ARP Carburettor Studs Will Assist You In Gasket Placement And Help You Position The Carburettor On Your Manifold. These Studs Have A Unique Nut-Starter Radius That Helps Prevent Cross-Threading. They Are Available In A Variety Of Materials - Finishes And Lengths-And Most Kits Also Include Washers And Hex Nuts.