MIL-SPEC · Electronic Components
NAS4121-370B
Heat Sink, Electrical
Part NumberNAS4121-370B
ManufacturerMIL-SPEC
AvailabilityAvailable to order — request a quote
Specifications
NSN5999-01-384-2619 (NSN)
Federal Item NameHEAT SINK,ELECTRICAL-ELECTRONIC
Federal Supply Class5999 — Miscellaneous Electrical Components
Overall Length0.739 INCHES MINIMUM AND 0.761 INCHES MAXIMUM
Test Data DocumentMIL-H-87111JAMIL-H-87111/5 SPECIFICATION (INCLUDES ENGINEERING TYPE BULLETINS, BROCHURES,ETC., THAT REFLECT SPECIFICATIO
Surface Treatment Document And ClaMIL-A-8625 TYPE1 OR 2 MIL SPEC SINGLE TREATMENT RESPONSE
Accommodated Device Mounting Hole1
Surface TreatmentANODIZE
Material Document And ClassificatiMIL-H-87111 MIL SPEC SINGLE MATERIAL RESPONSE AND MIL-H-87111/5B MIL SPEC SINGLE MATERIAL RESPONSE
MaterialALUMINUM ALLOY
Mounting Facility Type And Quantit1 UNTHREADED HOLE(S) SINGLE MOUNTING FACILITY
Overall Height0.358 INCHES MINIMUM AND 0.392 INCHES MAXIMUM
Unthreaded Mounting Hole Diameter0.139 INCHES MINIMUM AND 0.161 INCHES MAXIMUM SINGLE MOUNTING FACILITY
Body StyleHORIZONTALLY MOUNTED
ESD/EMICode A — ESD/EMI sensitive item
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
Every shipment inspected on receipt · ISO 9001:2015 · ANSI/ESD S20.20 · ERAI member since 1998 · GIDEP participant
Frequently asked
Is NAS4121-370B available?
We can source NAS4121-370B 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 NAS4121-370B by MIL-SPEC obsolete or end-of-life?
We specialize in obsolete, end-of-life, and discontinued components. If NAS4121-370B 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 NAS4121-370B?
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 NAS4121-370B?
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.