Rare New Old Stock (NOS) E424 triode preamplifier valves from Philips, manufactured in the late 1920s in The Netherlands. These are among the earliest production runs of the E424 type — featuring the iconic globe shape, brown bakelite base, and large mesh plate construction.

This is the original “first type” E424, selected for high-end broadcast and laboratory equipment of the interwar period. Each unit has been preserved in pristine condition and individually tested for transconductance & emission over original datasheet specifications.

Key characteristics:

• Open mesh plate structure with fine wire grid
• Globe-shaped clear glass envelope
• Original brown phenolic base (early Philips standard)
• Low noise and smooth harmonic response — ideal for vintage audio restoration
• Extremely rare as matched sets due to age and fragility

Available as matched pairs or matched quads upon request, with full documentation and provenance.