The Rezzin Ceiling Diffuser Model RZ500 comes with removable, multisize collars, and is available in two-way corner, three-way and four-way deflections. The product has a spring-loaded damper that locks in place after adjusting and a removable core for cleaning or service. The RZ500 also features a ratcheting clamp system that requires no tools when installing the diffuser to drywall or ceiling tiles.

Hart & Cooley Inc., 500 E. Eight St., Holland, MI 49423; (616) 392-7855; fax (616) 392-7971; www.hartandcooley.com.