Kroil Original Penetrant Oil

Kroil is the connoisseur's penetrant — the one machinists whisper about. Its molecular structure is engineered to creep through microscopic openings of one-millionth of an inch. When everything else fails, Kroil goes deeper.

Kroil is the product other penetrants are measured against, and with good reason. Its proprietary formula achieves a surface tension so low that it creeps into gaps of one-millionth of an inch — a level of penetration that borders on the theoretical. Machinists and gunsmiths have sworn by it for decades because it handles the jobs where lesser products fail completely, working its way into microscopic fissures in seized threads and corroded interfaces with an almost unsettling thoroughness that justifies every penny of its premium price.