Conductivity Test Pen, Grounding Tester, Continuity Tester for Grounding Mats, Sheets, Pads, Blankets, Pillow Cases. Use to Test Effectiveness of Earth Connected Products.

This pen works well to let you know that your mat is conducting as you would like for it to work. It is very easy, simply touch the double prongs directly to the mat and the top of the pen will light up. You may have to remove a cover off the double prong but after using the pen it is easy to slide the cover over the prong to put it away for the next time.

Works great, worth it!

Didn’t light up at all, I don’t see how to change the batteries, requested refund. Doesn’t do anything

It's a simple-to-use test for my grounding sheet.

This product worked exactly as stated, was low cost and what I needed.

What you're getting isn't anything overly complicated, but it works. You're completing a circuit powered by the button batteries that are provided and already inside; if the light comes on, electricity can flow through the object. Disassembly is simple, you pry open the plastic red lid, and remove a small plastic circle at the base of the two metal rods that help hold them in place. Everything inside and out looks as shown in the product photos. With mine, the rods themselves were uneven, and I didn't have as much luck pressing them straight down to test over holding them at an angle. Regardless, it works well enough as does as advertised.

It was very simple, just take the cap off of the prongs and apply the prongs to the grounding mat. If the light comes on, it is conductive!!

Most grounding testers were about $20, scrolled a little further to see this handy pen for $8.99. Wasn’t sure if it was a piece of junk or not but since it was returnable, I decided to take a chance and it really worked very well. No plugging anything in, no kit to figure out, just take the cap off the pen and touch it to your grounding fabric and voilà, Results!