Spotcheck® SKD S2, Solvent Based Developer, Pail, 5 gal no checkout Heavy duty grade torpedo level is Heavy duty grade torpedo level is up to the task under the most demanding jobsite conditions Durable die cast aluminum body Features 1 Brass construction provides long service life Non interchangeable oxygen and fuel gas connectors Instant closure on reverse flow check valves Spring loaded locking mechanism responds to fingertip action and achieves a gas tight connection Double seal socket connection on second seal ready to use solvent developer Suspends white developing particles in a fast drying solvent Produces opaque white coating that provides excellent contrasting background for penetrant indications Non halogenated