Also , the review: "It's an OK magic trick" ... this is NOT a stand-alone trick, it's a UTILITY DEVICE which can be used for dozens of different effects. If you look in the older magic books like The Tarbell Course or Rice's Encyclopedia of Silk Magic , or older magic magazines like Genii or New Tops, etc. you will find many, many routines that utilize a mirror glass. U.F. Grant's booklet "35 Miracles with a Mirror Glass" is another resource. With any utility device like this that needs to appear to be an ordinary item , you have to ask: Does it look good ? Does it look like an ordinary item (i.e. an ordinary , everyday drinking glass) ? Is it deceptive ? With a device like this it matters what it looks like. There are many cheap , poorly made versions of this device on the market that look exactly like what they are (you can pretty much see what the gimmick is) , but as with all of Bazar de Magia's trick glass products this one is well made. I would recommend it. But don't think of it as a single trick, it's a utility device.