Released in 1993 as part of the Captain Scarlet and the Mysterons toyline by Vivid Imaginations. The Mysteron Light Phaser was a gun like item that was a projector and voice changer all in one. We'll get to that shortly. The front of the box is very sparse, showing the show's logo with a picture of Captain Scarlet. There's a large picture of the product in action, with a smaller graphic showing the toy's functions
The back of the box has a blurb for the series. It also recycles the same graphic on the front of the box. The Light Phaser takes 2x AA batteries to make the projector work.
Taking the toy out the box, you can see it's in the shape of a gun with two triggers. Talking into the mouthpiece distorts your voice and is supposed to make you sound like a Mysteron. Pushing the bottom trigger makes a boom sound effect reminiscent of a gunshot or explosion. The upper trigger is what turns on the projector to make the classic Mysteron Rings appear.
The idea of the toy is that while playing with your Captain Scarlet toys, you could play the part of the Mysterons as well, by altering your voice to that otherworldly deep voice, as done by Donald Gray in the 1967 TV series, which can be heard here, as well as the trademark rings that go over people or objects to make them "Mysteronised"
It's not badly priced on the secondary market. I have found boxed versions going for about £25, but you can also get one in the Cloudbase gift set