Black Swan's All Purpose Pipe Dope is a yellow, soft-set, non-toxic pipe joint compound. Provides leak-proof resistance to high pressure, temperature expansion, contraction and extreme vibration. Excellent food and potable water systems. NSF Certified. Our All-Purpose Pipe Dope is designed to fill tiny cracks and voids in imperfect threads to help ensure leak-free and pressure tight joints. All Purpose Pipe Dope also acts as a lubricant which permits low torque make-up and easy disassembly without stripping threads.