SATCO Lighting S21407 16W LED PL 4-Pin, 5000K, 1850 Lumens, G24q Base, 50000 Avg Rated Hours, Vertical, Type A, Ballast dependent

The S21407 is a Type A, ballast dependent lamp. It runs off the existing fluorescent ballast already in the fixture, so it drops into the socket with no rewiring. If the ballast has failed, this lamp will not light. In that case you want a ballast bypass (Type B) lamp and direct wiring to line voltage instead.

No. The S21407 uses a 4-pin G24q base, which only seats in a 4-pin socket. Two-pin CFL sockets use a G24d base and the keying will not accept this lamp. Check the socket for four pins before ordering.

The S21407 is specified as a vertical lamp. That is the burn orientation it is built for, typical of downlight cans and vertical-socket PL fixtures. If your sockets hold the lamp on its side, such as in a wall sconce or a horizontal PL troffer, specify a horizontal version of the lamp instead.

5000K reads as a crisp, daylight white. It is the usual pick for parking garages, stairwells, back-of-house, and shop areas where you want high visual clarity. For tenant office space, lobbies, or hospitality where a warmer look is expected, most buyers standardize on 3500K or 4000K instead. Mixing color temperatures in one corridor will be obvious, so match whatever is already installed.

Order by Satco part number S21407. It ships in a frost finish, which diffuses the LED sources so you do not get hot spots through an open reflector or a clear lens.

Dimming on a Type A lamp is controlled by the ballast, not the lamp. The S21407 is ballast dependent, so behavior on a dimming ballast is not something to assume. For dimmable LED PL performance, the reliable path is a ballast bypass lamp wired to a line voltage dimmer rated for LED loads.