The XK-4 is the budget priced alternative to the XL-4, which was built in New Jersey USA.
Metal-necked basses have always been of interest as they naturally offer greater stability during the instruments life. However the nature of metal is that it's initially cold to the touch and as it gradually absorbs heat its dimensions alter and in some circumstances this can affect the tuning.
Larry Hartke designed the XK-4 knowing these pitfalls and came up with the ingenious idea of giving the aluminium neck a maple shell. So whilst the inner construction of an aluminium T-Bar welded to the chrome plated headstock is pretty innovative, the feel is far more conventional if somewhat substantial.
So you get an extremely stable neck, a futuristic looking headstock but a conventional feel (plus the added benefit of superior sustain - according to the manufacturers, at least). Although the pickups are passive the 2-band active EQ gives this a lot more kick in the sound.
The chunky and solid Schaller bridge proves to be the perfect choice here as its chrome bulk matches the headstock beautifully. A 5-string with a pair of J-type pickups was also produced.