OTC Tools OTC 4017 Dualmaster Jr Two Stage Hand Pump Assembly. OTC Tools. Here's two-stage flexibility at a popular price. These pumps have extra-large reservoirs and permit use with large hydraulic rams or in multiple small ram applications. Compact and lightweight, these rams deliver... providing high oil volume for rapid ram approach and return. Then they automatically switch at 300 PSI to the high pressure, low volume stage for high force applications. Both have a large, non-vented reservoir with safety relief valve to prevent over-pressurization of the reservoir. Piston stroke is 3/4 inch, maximum handle effort is 130 lbs. at 10000 PSI. Specifications: Pump with a 4-way valve for use with double-acting rams. Delivers 2.6 cu. in. of oil per stroke in low pressure stage. 125 cu. in. usable reservoir capacity. 3/8 inch NPTF oil port. Email for product availability.