The device consisted of a blocky base unit, sample hose and shoulder strap. It expelled minute quantities of air, providing just enough pressure that suction could be applied to draw in whatever material was nearby. It operated on a continuous cycle until its air supply was exhausted.
In 2267, Leonard McCoy and Montgomery Scott used vacu-lators to collect gas samples from the tail of Sanduy's Comet while the USS Enterprise maintained close proximity. McCoy ran out of samples during his analysis, requiring a second trip into the comet's tail to get more samples. (TOS comic: "A World Gone Mad")