This company offers bases for secure mounting of rooftop equipment. Each base is custom-made to the configurations of the units to be used. Available options include a built-in roof pitch, extra height for insulation of sound traps and a pressure-treated wood nailer. All bases are welded and shipped in one piece, if possible.

Thybar Corp., 913 S. Kay Ave., Addison, IL 60101; (800) 666-CURB; fax (630) 543-5309.