| Open Door Productions (Sumter, SC)
|
| Operation Usa (Culver City, CA)
|
| Ophir Corporation (Littleton, CO)
|
| Ops A La Carte Llc (Santa Clara, CA)
|
| Optimized Devices Inc (Pleasantville, NY)
|
| Opto 22 (Temecula, CA)
|
| Optrol Inc (Raleigh, NC)
|
| Ora Sure Technologies Inc (Bethlehem, PA)
|
| Orbeco Analytical Systems Inc (Farmingdale, NY)
|
| Orbit/Fr Inc (Horsham, PA)
|
| Orion Development Corp (Gurley, AL)
|
| Osi Optoelectronics Inc (Hawthorne, CA)
|
| Ottotek (Tucson, AZ)
|
| Owens & Assoc Inc (Mount Pleasant, SC)
|
| Owlstone Nanotech Inc (Saddle Brook, NJ)
|
| Oyo Geospace Corp (Houston, TX)
|
| Ozark Laser Systems (Springfield, MO)
|
| P H Tool Co (Des Plaines, IL)
|
| P S Analytical Inc (Deerfield Beach, FL)
|
| Pac Lp (Houston, TX)
|
| Pacific Instruments (Concord, CA)
|
| Pacific Precision Labs Inc (Chatsworth, CA)
|
| Palmeri Electronics (Garfield, NJ)
|
| Pamark Co (Grand Rapids, MI)
|
| Panalarm (Skokie, IL)
|
