I believe this product is from the late Showa 50s (1975-1989). Although it is unused, it has likely deteriorated due to long-term storage in a warehouse. There are some light stains on the surface. The material is a combination of woven bamboo and plastic packing straps, which enhances durability compared to products made only from natural materials. Dimensions are approximately 70cm wide, 60cm long, and 12cm deep.