MIL-SPEC · Electronic Components
3D21B
Electron Tube
Part Number3D21B
ManufacturerMIL-SPEC
AvailabilityAvailable to order — request a quote
Specifications
NSN5960-00-577-1433 (NSN)
Federal Item NameELECTRON TUBE
Federal Supply Class5960 — Electron Tubes
Tube TypeTETRODE
Nondefinitive Spec Std Data3D21B(MIL-E-1/1132A NAVY) TYPE
Cancelled NSN1440-00-969-9380 (cancelled)
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 3D21B available?
We can source 3D21B 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 3D21B by MIL-SPEC obsolete or end-of-life?
We specialize in obsolete, end-of-life, and discontinued components. If 3D21B 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 3D21B?
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 3D21B?
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.