Some additional evidence for discontinuity

A sleeve assembly for forming a lined opening in molded structures made from concrete or the like, the sleeve providing the lining and being held in place during formation of the structure by a pair of conical sleeve lock elements having extended tapering surfaces for supporting sleeves of a variety of sizes, the sleeve lock elements preferably being held in place upon forming panels for the structure by means of a central stabilizing rod penetrating through the sleeve lock elements and the panels. An additional embodiment of the sleeve assembly is adapted to be secured to a generally horizontal panel upon which a molded structure such as a floor is formed.