EISCO 7 Piece Cork Borer Set - Includes 6 Cork Borers and One Steel Ram Rod - Nickel-Plated Brass with Plastic Handles - Useful for Both Rubber Stoppers and Corks

I use these to core potatoes for a middle school osmosis science lab. They work perfectly!

They work as intended.

Used largest borer to make a hole in a rubber stopper.

They seem to be well made, especially for the price. However, they were co dull I couldnt push them even halfway through a stopper. I sharpened one and it cuf just fine. I use glycerine to lubricate the cutter when boring. If you don't mind sharpening them (which you have to do anyway, eventually) I think they are a good deal.

The metal is so thin that on an older dry cork the edges of the cutting portion just rolls in instead of cutting. They are very weak