Seen in many episodes of TNG.

I purchased this on E-bay.

This is one of those rare, mass-produced props that is actually pretty decent. This phaser was made by a company named IPI back in the nineties. It's injection molded plastic with rubber grips. It has a laser pointer, and makes a decent phaser noise. It comes in a felt carrying case and an owners manual. I heard through the grapevine that this item was made from studio molds that were cleaned up. I haven't really done a side by side comparison, but this product is very uniform, even and well made.