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2D21 Thytron Vacuum Tube. Designed to be used in relay and grid-controlled rectifier applications. MFR: RCA, Westinghouse, Sylvania, GE, Tung Sol, National. SKU: 2D21. New old stock. No longer available for export.
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2D21 National Eletronics NOS NIB electron tube red box made in England, For Old Electronics, Mounting Type: Circuit at best price in Mumbai
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2D21 TUBE -Experience Pure Analog Sound with our Premium Vacuum Tube for High-Fidelity Audio Systems – Big River Hardware
![2D21 National Eletronics NOS NIB electron tube red box made in England, For Old Electronics, Mounting Type: Circuit at best price in Mumbai 2D21 National Eletronics NOS NIB electron tube red box made in England, For Old Electronics, Mounting Type: Circuit at best price in Mumbai](http://5.imimg.com/data5/SELLER/Default/2022/8/NY/TR/DS/3551768/2d21-e.jpg)
2D21 National Eletronics NOS NIB electron tube red box made in England, For Old Electronics, Mounting Type: Circuit at best price in Mumbai
![Tube à vide RCA 2D21 pour émetteur Collins KWS-1 tube miniature de thyratron à 7 broches - Etsy France Tube à vide RCA 2D21 pour émetteur Collins KWS-1 tube miniature de thyratron à 7 broches - Etsy France](https://i.etsystatic.com/7035969/r/il/12f843/2789239932/il_fullxfull.2789239932_aho3.jpg)