Black, lightly padded nylon field vest by japanese brand men's ba-tsu (circa 1990s). It has a zipped front, multiple front pockets, and a grosgrain belt which can be adjusted via press studs.

No marked size (JP mens/unisex)
Check measurements to confirm fit
All measurements taken flat

Shoulder width: 41.5 cm
Width (at underarms): 58 cm
Length (neck to hem): 59 cm
Hem width: 59 cm

100% nylon outer, 100% polyester lining and fill
Made in korea
C. 1990s

More items by ba-tsu here.