I think they must be a winter season, as the material is quite heavy, but they fit well and appear to be of excellent quality. The outer shell is polywool, a blend of wool and polyester which nevertheless looks great, especially given the price.
“Jam trousers” or “Ruperts” make a great addition to any Mod wardrobe. But if you’re looking for a strongly versatile pair of dogtooths - go for these ones.