Are these the normal 6' lamps that have 1 pin on each end of the lamp, or are they the HO type that has recessed pins on the end?
Just asking to determine the light output.
You might be able to find a 6' LED tube, but it will likely be from some no-name manufacturer that wont be in business in a year or two.
Either way, I wouldn't use a 6' LED tube to replace them, just because 6' tubes are fairly rare. If it was my space, I'd replace the fixtures. At 16', you could use a new LED highbay in the range of 12,000 to 16,000 lumens and you'd have vastly improved lighting.
If you choose to keep your strip fixtures, you could use a "tandem kit" to modify it so that it takes either 4 3-foot tubes, or 2 4-foot tubes plus 2 2-foot tubes. I'm not in love with either of these options either, since 3' tubes are about as common as...well...6' tubes.
That's why, in your case, I'd consider using new fixtures.
Good luck,
CD
