The Smoke Pen works like a mechanical pencil where the user inserts a patented smoke-emitting wick into the pen, adjusts the wick to provide 3/8 inches of exposed wick, then lights the wick with a match or lighter. The pen provides a continuous trail of smoke, which can then be extinguished by replacing the protective cover. The nontoxic, cool-burning emitter is designed for air balancing, verifying ventilation, testing smoke alarms, and tests for negative or positive pressure.

Regin HVAC Products, 273 Canal St., Suite 222, Shelton, CT 06484; (800) 394-2739; fax (203) 922-0158; www.regin.com.