Etches on all conductive materials, brass, aluminium, copper, steel etc. The last photo shows marking out on HSS steel with maximum voltage setting. It only needed half output voltage to mark, but the sparking did not show up in that photo and I wished to show it working.
Various input voltages are selected by the bridge at the back of the unit. There are a few spare styli (styluses) with the unit, some used but still serviceable.
This unit was used in an engineering company to mark turning form tools with the part number, before storing. Although not large, the unit is solidly built and weighs around 4 kilos. The item "Actograp Electric Pen. Metal Jewellery" is in sale since Wednesday, March 24, 2021.This item is in the category "Business, Office & Industrial\Hand Tools\Other Hand Tools". The seller is "svenskal" and is located in Ware, Hertfordshire. This item can be shipped to United Kingdom.