Seiko built its first Alpinist in 1959 specifically for Japanese mountain climbers, making it the brand's first sports watch, predating its dive watches by years. The SPB377J1 is the first automatic Alpinist to carry a GMT complication, built around the Cal. 6R54 with a 72-hour power reserve, enough for three days on the mountain without winding. The blue sunray dial carries the original's wedge-shaped markers, bold numerals, and stylized hands, with a red-tipped GMT hand tracking a second time zone against a 24-hour scale on the bezel, and LumiBrite hands and markers that stay readable before dawn on an alpine start. The inner rotating compass bezel is a functional navigation tool, usable with the sun to calculate bearings. The 39.5mm stainless steel case runs 13.6mm thick, fitting easily under a glove to protect hands in harsh conditions.