Kay-made resonator banjos of this type are not that uncommon, but it's quite rare that one actually sees a plectrum model with its long scale (27 1/4" on this one), 4-string neck. Traditionally these are tuned CGBD low to high, but a lot of folks tune them DGBE "Chicago" style these days. I use a set of light (9s) 5-string banjo strings and leave the high drone as a spare high E string for this tuning.
The design of this banjo is really simple and dates back to Kay's mid-late 1930s banjos that began to use coordinator rods and neck-angle-adjuster plates. I'm fairly certain this is a mid-50s Kay and it's mostly original.
My uncle-in-law down in Connecticut owns this banjo and sent it up with my in-laws over the weekend to get it spruced up. I don't know what direction he necessarily wanted to go in entirely, but I did all the work it needed to be an excellent performer. That included a a fret level/dress, side dot install, some modification to the rim (which can be seen in this post), a set of new 4:1 geared tuners, regluing his aftermarket pickup sensor in a slightly better spot on the head, compensation of the bridge, and a general setup. The neck is almost dead straight at tension (1/64" relief overall) and it plays spot-on with 1/16" action at the 12th fret.
The Old Kraftsman name was a brand for the Spiegel mail-order catalog house.
The original brass frets still have decent height left, too. The board is rosewood and the neck is either maple or poplar. It's awful hard to know with all the black paint.
Due to the quick job, I'd forgotten to remove the owner's tape from the rear of the resonator.