have no idea... wife bought them at home depot they were not cheap but just twisted ino fixture and done. I am going to do dame in some of the rooms at SMECC museum too. I like a simple fix and this was! In a message dated 3/7/2017 12:43:24 P.M. US Mountain Standard Time, cctalk at classiccmp.org writes: On 3/7/2017 11:04 AM, Ed via cctalk wrote: wight into I've asked about those and have no sources of such. They do have to work thru ballasts and deal with starter issues that are no longer relevant, unless you remove and rewire the ballasts / starters out of the old fixtures. The things I've seen are the same form factor as a 4' dual tube dual 40 watt fixture with 110 in and light out. Pull and toss an old dual tube fixture and replace with new LED. But I've not seen the tube solution. I've got a couple of spots the tube thing would be desirable, but no source of such. If you do have a source I'd be interested. thanks Jim