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WPI World Precision Instruments Omega-B Omega Tip

World Precision Instruments WPI 121 Window Discriminator 121-G Made in USA

World Precision Instruments WPI EVC3-1 Preamplifier

WPI World Precision Instruments M-707 for Patch Clamp, Data Acqn, Neuroscience

Vintage Grass Instruments Model 8A5 (Untested)

World Precision Instruments WPI EVC3 Preamplifier

World Precision Instruments WPI EVC3-A Preamplifier,Cable Assy 5443, Stand att.