The spacers are available in nylon and aluminum, and are precision machined to space circuit boards 0.6 in. apart. The stand-alone stacks can serve as ultracompact bus boards, without the need for backplanes or birdcages. The stacking spacers are ≥/-in. diameter, have a ≥/-in.-long 4-40 male thread on one end, accept a 4-40 thread screw on the other end, and have available mating screws and hex nuts in both nylon and aluminum. The spacers work with over 100 different PC/104 ultracompact bus-board modules.

RAF Electronic Hardware, 95 Silvermine Rd., Seymour, CT 06483, (203) 888-2133, www.rafhdwe.com