(UU-136)-Insert (plugs for thermactor holes in head) - 5/8" - 11 x 7/16" - 14 x 1 1/8" , STANDARD PART
(UU-136)-Insert (reducer for thermactor holes in head)-5/8"-11 x 7/16"-14 x 1 1/8" , STANDARD PART
(UU-136)-insert(used in front and rear of cyl. head)-5/8"-11 O.D. thread x 7/16"-14 I.D. thread , STANDARD PART