A plastic explosive is a high explosive material that is soft and can be molded by hand. This allows the user to fit it into cracks and concentrate it directly on structural weak points. Common modern plastic explosives include Semtex and C-4.
Plastic explosives in Wasteland are used like TNT, to blast open doors and rubble to allow passage. Plastic explosives work in places that TNT won't, like on the crystalline wall in the vault on the second level of the Sleeper Base. It is noteworthy that Sabot Rockets, LAW Rockets and RPG-7s can also be used in places where TNT is not effective; however, Plastic explosives are far cheaper.
When used in combat, plastic explosives function like chunks of TNT or grenades, but are more effective than either.