Thorn 2DFV21

The Thorn 2DFV range expands a little more. All 2DFV bulkheads I've ever seen have been with a black base, coming in 16w and 28w wattages. Breaking the range down, we have:

Thorn 2DFV16, by far the most common, having a black base and a opal cover.
Thorn EFP3, taking a single 4w tube in non maintained mode, with a slightly clearer bowl than usual.
Thorn 2DFC16, the far rarer and much more sought after prismatic version of the 2DFV16, which as of now is the only one I'm looking for to complete the range.
Thorn 2DFV28, for 28w 2D lamps, the final one in the range, or so I thought.

Then theres this, the 2DFV21, coming with a unusual white base. Its a variant I never even knew existed, and I have to admit, it looks very odd, but overall cleaner with the white base rather than the black. Coming NOS, it even sports its original lamp. Overall a unusual and rare find.