This is used 66chain model. In contrast to the 66single model, the late 66chain model is said to have no vintage color fade, but this one seems to have some vintage characteristics like a little vertical drop due to in the year 1978.
The paper patches are indistinguishable from the 66single's one and redline's one. A perforation of the tear-off tag remains on the right side.
It's hard to tell from the photo, but you can see the single-digit number on the shrinkage ratio faintly, so it's not redline model (10% shrinkage) but 66chain model.
The numbers on the third line from the top are "7, 8 and 6", indicating that it was made at the factory on July 6, 1978.
Near-square-shaped back pocket. The arcuate stitch is relatively well-balanced on the left and right sides and has a shallow angle.
back pocket (back)
It is stitched with chain stitching, and judging by the shrinkage rate written on the inside tag, it can be determined to be 66chain model.
The type that has a lot of pots and pockets. The side of the top button is parallel stitching.
Coin pockets are used vertically and the other cloth is used horizontally. The back of the coin pocket is chain stitched.
You can see a slight vertical drop. Even if you actually look at it, it's hard to distinguish it from the 66single model. It's very natural and I personally like it.
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