In general, it is a miniature blaster that has a stylus-type hand piece with a nozzle opening of about a pencil point, which is the reason that some models are actually called pencil blasters. As with all blasters, big or small, there are only two types: siphon or pressure blasters. One can easily detect the difference by the way the blaster is constructed.
The siphon-type micro blasters have some kind of container (usually small) directly attached to the stylus/hand piece, from which the introduced air siphons the abrasive into the air stream and then propels it through the nozzle at the glass. These types of blasters usually have either a push button, like on an airbrush, or a small trigger for operation.
Pressure-type micro blasters have a separate larger container in which the abrasive is filled that is set under pressure itself, and then the abrasive is mixed with the air before being hurled at the glass through the nozzle. Most of the pressure micro blasters have foot pedals for easy on-off operation.
All in all, these small blasters are a welcome accessory to any sandcarving studio, but I would not rely on such a blaster for my main blasting tool, unless you only do small designs and names on glassware, and that mostly by surface etching; otherwise, you will get frustrated rather quickly.
—Professional Glass Consultants
