Using refillable wicks, the device works like a mechanical pencil; where a wick�can be inserted into the pen, leaving a 10mm trace that can subsequently be�ignited by either a lighter or match. The patented design of the wick ensures�a continuous and consistent smoke trail, helping simplify ASD system smoke�testing. Once smoke testing has been completed, smoke can be quickly�extinguished by replacing the smoke pen lid, leaving the wick ready for reuse�at a later date. The Smoke Pen comes with 6 replacement wicks, and a�separate refill pack is available as a spare part.