I acquired my Field & Trek eight used on eBay from Michael Buchan in 2008.
The Field & Trek is forged from aluminum alloy and then soft anodized. Mine is 146 mm. tall, 76 mm. wide, and 16 mm. thick. The rope hole is 51 mm. high and 51 mm. wide. The top center thickness is 12 mm. The shaft length and width are 46 mm. and 26 mm., respectively. The eye measures 26 mm. by 26 mm. My eight weighs 128 g.
One side is stamped "field & trek" on the shaft and "02 03" near the top. On the other side of the shaft, I can faintly read "KN 35."
The Field & Trek is a typical example of a full sized, forged, aluminum figure eight, and is essentially identical to many other brands.