This is a Japanese-made S. Yairi Model No. YD-306, which had a list price of 120,000 yen at the time. The serial number on the neck block starts with 10*** (five digits), indicating it was manufactured around 1977. Both the sides and back are solid rosewood. This model from this era does not have an adjustable truss rod. My assessment of the condition is a 5-point scale: [Appearance 3-] [Sound 5]. Main specifications of the S.YAIRI YD-306: Top: Solid Spruce Sides & Back: Solid Rosewood (3-piece back) Neck: Mahogany Fingerboard & Bridge: Striped Ebony Tuners: Schaller M6 Rotomatic Gold It is characterized by its careful construction and a brilliant sound with many overtones, making you feel happy just holding it. Materials of significantly higher quality than the price suggest were used. The condition of this instrument is described below. The top has numerous cracks and weather checking, and as shown in image 9, there is a split and misalignment in the soundhole area. Necessary patching and adhesive repairs have been done. The sides and back have light scratches and dents, but no cracks in the wood are visible. The back of the neck and the headstock edges also show paint damage. The neck heel appears to have been glued and repaired for separation before it was acquired. The original tuners have some rust on the plated surface, but about 70% of the gold plating remains, and the movement is smooth. The string height is approximately 3.0mm on the 6th string side and approximately 2.5mm on the 1st string side at the 12th fret, adjusted to a standard height. The saddle has about 3mm remaining at its highest point, and can still be lowered slightly. The nut width is approximately 43mm as measured with calipers. The frets have more than 70% life remaining. There are no dents or wear on the fingerboard surface caused by fingernails. The adjustable truss rod is embedded and cannot be adjusted. There is no lifting of the bridge, and no bulging or deformation of the top. There is no tobacco smell or other unusual odors inside. Although there are noticeable repair marks on the top, it is in fairly good condition. It will be shipped in the Yamaha Rocket-shaped hard case shown in the photos. Shipping is included via Kuroneko Yamato Mercari delivery service.