A drill tool includes a bit body, at least one bearing shaft extending from the bit body and a cone mounted for rotation on the bearing shaft. An surface cleaning apparatus is also provided that includes an air flow path extending from the cleaning head air outlet to the air treatment member air inlet and comprising a flexible electrified air flow conduit and a handle assembly drivingly connected to the surface cleaning head with a light source disposed on the handle assembly. The device is hollow, having at least one vertical channel and at least one horizontal channel drilled from the outer wall of the device to the inner vertical channel. Methods of manufacturing and operating the apparatus and systems are also described. In particular, the present invention provides a heterodimeric polypeptide comprising an immunoglobulin heavy chain and a fusion protein comprising an immunoglobulin light chain and an Fc molecule.