This prop was used (worn and wielded) by the Sheldon Cooper character (Jim Parsons) on The Big Bang Theory. The prop was part of his costume as Mr. Data from Star Trek: The Next Generation.
It was used in Season 6, episode 13, 'The Bakersfield Expedition'.
This prop began life simply as a Master Replicas Boomerang Phaser from Star Trek: First Contact and was chosen by TBBT Executive Producer and Co-Creator, Bill Prady, for use by the Sheldon character.
Pictured with the prop is Scott London, Property Master for TBBT, in his workshop in the back of Stage 25 at Warner Bros.
Also pictured is a screen-cap showing the Sheldon character wearing the phaser on his right hip.
UPDATE: This same prop was re-used later in the same season by Jim Parsons in 'The Spoiler Alert Segmentation' while he was packing up Leonard's collectibles and describing them to Amy for her to make a list.
