Solinst Model 122M [110942] Mini Oil/Water Interface Meter With P8 Probe & Metric Increments, 25m. The Solinst Mini Oil/Water Interface Meters give clear and accurate measurements of product level and thickness in wells and tanks. Determination of both light (floating) non-aqueous phase liquids (LNAPL) and dense (sinking) non-aqueous phase liquids (DNAPL) is quick and easy. The Model 122M Mini Interface Meter with PVDF laser marked cable is a convenient small version, which can easily to fit in a backpack, or an optional custom mini carry case. It uses narrow laser marked PVDF cable, in 80 ft or 25m lengths. The Mini Interface Meter enhanced electronics include automatic circuitry testing; 300 hours of on-time battery life; clear signals; and high accuracy. The circuits are powered by one standard 9V battery housed in easy-access drawer in the faceplate.The 122M uses the P8 Probe, which is 5/8" in diameter (16mm) and stainless steel construction. It is pressure proof up to 500 psi. The beam is emitted from within a Hydex cone-shaped tip. The tip is protected by an integral stainless steel shield, and is excellent for the vast majority of product monitoring situations. The 0.12" (3mm) coaxial cable has a durable PVDF jacket with permanent laser markings every 1/100 ft. or each millimeter. The cable has a braided copper outer conductor, a stranded stainless steel central conductor, and a smooth chemical-resistant surface that is easy to decontaminate.