P-CADD
The P-CADD or Polymer Capsule Deployment Device is a specialized piece of Starfleet equipment used by personnel when operating in Hostile planetary environments, where the use of a phaser or energy weapon can not be used for breaching structures or compartments, due to environmental concerns.
The device is a reminiscent of an old-style projectile weapon. The weapon utilizes compressed noble gasses to launch a capsule at a distance of up to 100 yards with reasonable accuracy.
This capsule contains a special polymer which causes a rapid endothermic reaction which flash-freezes alloyed metals and makes them shatter as they contract.
These devices are sometimes carried by Starfleet Rangers assigned to special operations.
In 2414, the crew of the USS Rosenante used P-CADDs on the surface of the Rogue Planet Solyon when they were required to breach the floor of an artificial volcanic vent in order to allow them to reach an artificial facility buried beneath the surface of the planet. In this case the operation was in a particularly oxygen rich environment, and the operational planners were concerned that the use of phasers in this area would cause an explosion.
The P-CADD was first seen in the USS Rosenante Mission The Third Law