NPN PNP Signal Converter, MRI-24TR/INV PLC Sensor Polar IO Level Conversion Module, PNP to NPN Signal Converter Relay: Amazon.com: Industrial & Scientific
Transistor Kit 10 Value 200pcs NPN PNP Power Transistor Assortment Kit, Transistors Box Pack for BC337, BC327, 2N2222, 2N907, 2N3904, 2N3906, S8050, S8550, A1015, C1815 by Kulannder: Amazon.com: Industrial & Scientific
Transistor Tester, Multi-Functional Inductance Capacitance Resistance Electronic Meter TR LCR ESR for NPN and PNP Bipolar Transistors: Amazon.com: Industrial & Scientific
Amazon.com: Digital Counter, Easy Connection NPN PNP Signal Input Stable Electric Counters Auto Detection for Industrial Control : Industrial & Scientific
Hilitchi 24-Values 2N2222-S9018 / BC327-BC558 NPN PNP Power General Purpose Transistors Assortment Kit - Pack of 840: Amazon.com: Industrial & Scientific
Slim DIN Rail Mount NPN to PNP/PNP to NPN Sensor Logic Signal Converter Module: Amazon.com: Industrial & Scientific
Bridgold 10pcs(5pcs 2SA1943+5pcs 2SC5200) PNP NPN High Power Matched Audio Transistor Silicon Precision,3-Pin.: Amazon.com: Industrial & Scientific