Ultraviolet Permanent Security Invisible Ink Pen

Great product, I have been using them for about a year in our business, to mark used items we dispose of via ebay, such as computers and parts, which we mark because some people will try to return their faulty part, pretending it if your one which has failed when first used... This allows us to mark the products before they are sold, and if a return comes in, we can quickly check with a UV Torch to make sure it really is the item we sent out to them! It has managed to catch out a couple of fraudulent buyers, who instantly backed down (went quiet) as soon as they were confronted regarding the security marking... Great product.

These are okay, I found I had to go over the marking a couple of times to get a decent result when I was later checking the results. They were cheap and you get 5 so plenty to mark all your goods. I was actually using them to create special effects for a halloween party with a blacklight. They worked well, but you really need to check the results especially on some plastics to make sure it's visible (under UV light).

Whatever these pens are needed for, marking up bank notes, marking personal possessions within your home/work/school or using in a nightclub as a smokers mark / vip mark, these pens are brilliant. They don't smudge unlike some of the thicker tip UV pens, they dry instantly and don't have the offensive smell. Good price, good delivery, arrived quickly.

Having heard of horror stories of thefts i decided that I would go savvy and UV mark all our electronic devices. This pack provides a reasonably priced pack of 5 pens. I would like to add that you probably only need one but for £1 extra it's always good to keep a few spare especially as someone in the house has a habit of losing pen lids and allowing them to go dry!

The first few markings were indistinct when viewed by UV lamp. However, things got better after about six times. I have only used these pens for a few weeks and they appear to work well. Whether they will be permanent remains to be seen. Writing on dark surfaces leaves a barely visible trace in natural light. Best results are on light surfaces; aluminium, silvery effect etc. where the marking are invisible in natural light but can be clearly seen under UV light.

They can be used without unduly showing under day/artificial light. But the markings hardly glowed when using a battery powered florescent tube UV light. The markings showed up well under a high powered LED UV torch. On some white surfaces the surface itself glowed more than the marking. I would recommend the markers where a you don't want it to be obvious & anyone looking for the markings has access to a strong UV emitter.

Marvelous clear writing and long lasting for once too. Highly recommended for security marking and black light notices. The tip is a little wide to use, but it is very effective. I have marked all my belongings with it just in case and I cant fault its use. I have bought some before from a different supplier that marked 5 items and ran out. Im still on my first one.

Used these along with UV torch for the kids to have a treasure hunt at Halloween. They worked perfectly! Kids had a ball finding the clues. Pens worked well and the ink stood up to the outdoor Scottish weather!