SATCO Lighting S21373 4W T6.5 LED, Frosted, Intermediate Base, 4000K, 360 Lumens, 120V

4000K is a neutral or cool white, noticeably whiter than the 2700K warm white most residential bulbs use and warmer than 5000K daylight. If the other lamps in the run are 2700K or 3000K, the S21373 will read visibly bluer next to them. For property managers standardizing a building, pick one color temperature across the fixture group rather than mixing.

At 360 lumens on 4 watts, the S21373 lands in the range of a 25 to 40 watt incandescent for output while drawing a fraction of the power. For appliance, cabinet, sign and decorative sockets where a small T6.5 tube lamp was used, that is a like for like swap on brightness. It is not a general room lighting lamp.

It runs direct on 120 volt line power. No external driver, transformer or ballast is needed, so it drops straight into a standard 120V intermediate socket. Do not put it on a 12V or 24V low voltage circuit.

Order by Satco part number S21373. That number pins the exact combination: 4 watt, T6.5 tubular, frosted, intermediate base, 4000K, 360 lumens, 120 volt. Satco runs many near identical small lamps that differ only in base type or color temperature, so the part number is the safest thing to put on a purchase order.

Frosted, yes. The coating diffuses the light so you do not see individual diode points through the glass, which matters in open fixtures, glass front cases and any socket where the lamp is in view. Frost is the only finish this T6.5 lamp comes in.

T6.5 is a tubular lamp roughly 6.5 eighths of an inch in diameter, a slim straight tube rather than a bulged globe. That narrow profile is why it suits tight enclosures like appliance housings, showcase and display fixtures, sign cans and exit lighting where a standard A shape will not clear the socket cup.