Dura-Gold Fiberglass Spot Scratch Brush Pen Tool, Pack of 3 - Clean, Sand, Scuff Surfaces, Remove Rust & Corrosion, Prep Sanding Auto Paint Scratches for Painting - Polish Metals, Cleaning Electronics

Worked well on my train motor armature. Got the gunk off

If these weren't so cheaply made I'd give them 5 stars. If you want really stiff hard bristles that will clean down to bare metal, these are the ones you want. A lot of others have soft bristles and are useless to me. Maybe the soft ones are good for jewelry, you definitely do not want to use these on jewelry! It will scratch the heck out of it.

Works great. And I like that you can twist it in or out, so you can protect the bristles.

Fast service great price

Have always used ProMotorCar brand Prep Pen and should never have tried these. Thought the price and quantity was a good deal. Boy was I wrong. Bristles are too soft to scuff affectively. After 30 seconds of aggravation they met my hammer and landed in the garbage can. After testing several Dura Gold products and always being disappointed, they will never find their way to my toolbox again!

There is no binder in the fibers so there is no strength in the brush. Pressure cannot be applied to the brush and work piece. I used alcohol with one of these brushes to clean solder joints. The alcohol wicked up the full length of the brush rendering it useless for any other task. I was given a scratch pen that would remove surface rust from tool steel. These brushes won't touch surface rust. These are all but worthless.

Fits in tight spots, but I really have to work at removing paint. It's very fine

As advertised