The Star Trek: The Original Series phaser rifle.
It was never actually named in the series, and was seen only in the episode "Where No Man Has Gone Before".
This is one of the few props for the original series made by a contractor. It was designed and manufactured by Reuben Klamer, who had invented the board game "The Game of Life" for Milton Bradley. Gene Roddenberry saw a prop gun Klamer designed for The Man from U.N.C.L.E., and contacted Klamer. Klamer made several designs (it's not clear how many), before Roddenberry signed off on the final version.
Klamer had only two weeks to both design and manufacture the prop. Working around the clock, Klamer and three assistants constructed the rilfe out of wood and painted it metallic blue/green. The prop also featured a hand-tooled aluminum barrel with dish end, spring-loaded trigger, sliding switch (left of the central top module) to adjust the setting, three plastic non-functional domed indicator lights (right of the central top module), inset plastic panels (yellow, orange, and red on both sides of the butt), and a top-mounted telescoping antenna (which looked more like a sight). The three "power packs" consisted of ribbed copper tubing in acrylic cylinders. The ends of the cylinders were painted either yellow, orange, or red (matching the three force settings). These could actually be taken off the weapon, and moved around. The rilfe came with a black, padded shoulder stock that could be rotated to function as a stock or a hand. The prop was 34 inches long, 14 inches high, and 4.5 inches wide.
For the phaser rifle's beam, the laser cannon animation from the original pilot, "The Cage", was reused.
The Watts race riots occurred in August 1965. As the riots came close to the Desilu studios where Star Trek was being filmed, producer Herbert F. Solow suggested to Gene Roddenberry that they brandish the phaser rifle to bluff the rioters and keep them at bay. Its use was not needed; the riots did not hit the studio.
Although Gene Roddenberry was initially enthusiastic about the phaser rilfe, his ardor quickly cooled. The phaser rifle had been used in some publicity photos of William Shatner by that time. That was the end of it, though: Roddenberry decided against using gun-like weapons on the series (he also banned the depiction of smoking), and the phaser rifle was returned to Klamer.
A replica of the phaser rifle was manufactured at some point in the 1980s by Paramount, and this replica was used in various exhibits, displays, and promotional tours. There may have been more than one replica made; one ended up in the possession of Sally Kellerman herself.
Klamer sold the original phaser rifle, along with his preliminary designs, blueprints for the final version, and receipts for payment, in April 2013. Estimated to sell for $50,000 to $70,000, it sold for a whopping $231,000 -- the most expensive Star Trek hand-held prop ever sold at auction to date.