The most popular back for the Morris W-40 is Jacaranda. This is an early 1973 model with a 3-piece maple neck... Early models are extremely rare and rarely appear on the used market! Although it's all plywood, it has the same specs as the top-solid S. Yairi YD304. The sound is similar and resonates nicely. The neck is almost straight (6th string at 12th fret is about 2.8mm), with no neck lift, and the frets are still in good condition, with no fret buzz. This is a vintage item, so please understand and purchase with no claims and no returns. Only listed on Mercari. Beware of malicious websites!