A sprinkler head conversion sleeve/base member made of durable plastic, comprised of a cylindrical sleeve having an opening at the upper end with an external thread for attachment to a gear driven sprinkler head. The lower end of the sleeve having an external thread for attachment to the internal threads of an in-ground sprinkler housing. The open bottom of the sleeve receives water from the lower chamber of the existing sprinkler housing with no direct connect to a pressurized water system, water enters from either the bottom or the side orifice with no additional plumbing. The sleeve also supports internal protrusions which facilitate the mechanical operation of a gear driven sprinkler head used in conjunction with the sleeve.
