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MIL-SPEC  · Electronic Components

RTH42ES121J

Resistor, Thermal

Part NumberRTH42ES121J
ManufacturerMIL-SPEC
AvailabilityAvailable to order — request a quote

Specifications

Federal Item NameRESISTOR,THERMAL
Federal Supply Class5905 — Resistors
Ambient Temp At Full Rated Power25.0 CELSIUS
Body Outside Diameter0.100 INCHES NOMINAL
Power Dissipation Constant In Mill2.5
Resistance Tolerance At A Specifie-15.0 TO 15.0 SIXTH RESISTANCE-TEMPERATURE POINT
Zero Power Resistance At Specified92.4 OHMS SECOND RESISTANCE-TEMPERATURE POINT
Zero Power Resistance Tolerance In-5.0 TO 5.0
Temp Points For Resistance Reading50.0 CELSIUS THIRD RESISTANCE-TEMPERATURE POINT
Inclosure TypeHERMETICALLY SEALED
Reference Temp In Deg Celsius25.0
Style DesignatorROD
Terminal Type And Quantity2 WIRE LEAD
ESD/EMICode B — ESD/EMI sensitive item
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RH Electronics, Inc. — independent stocking distributor since 1982.
Every shipment inspected on receipt · ISO 9001:2015 · ANSI/ESD S20.20 · ERAI member since 1998 · GIDEP participant

Frequently asked

Is RTH42ES121J available?
We can source RTH42ES121J even if it isn't in our active stock list. As an independent distributor we reach inventory outside the franchise channel — including hard-to-find and obsolete parts. Send us a quote request.
Is RTH42ES121J by MIL-SPEC obsolete or end-of-life?
We specialize in obsolete, end-of-life, and discontinued components. If RTH42ES121J has been discontinued, we can often source remaining stock or qualified alternates. Contact us with your quantity and target date.
How does RH Electronics verify parts like RTH42ES121J?
Every incoming shipment is inspected under our ISO 9001:2015 quality system — documentation, markings, and construction checked against known-good references. For deeper analysis, we direct work through accredited independent labs. We've been an ERAI member since 1998 and a GIDEP participant.
Can you find a cross-reference or alternate for RTH42ES121J?
Yes. Our team reads part numbers the way they were designed — decoding family, speed, temperature grade, package, and reliability level — to identify acceptable alternates when the exact part isn't available. Submit a quote request and we'll advise.