I acquired this eight from B&C Wunderwear in 1993.
The TZ eight is milled from stainless steel plate. Mine is 128 mm. tall, 88 mm. wide, and 14 mm. thick. The rope hole is 38 mm high and 63 mm. wide. The top center thickness is 13 mm. The shaft length and width are 10 mm. and 32 mm., respectively. The eye measures 56 mm. by 16 mm. The ears are 41.6 mm. long. My TZ eight weighs 488 g.
There are no markings on this eight.
The TZ eight is a variety of "midi" size figure eight with ears. Bob Handley milled this eight out of stainless steel. The TZ Eight is well made and wears well, but it is heavy and expensive. The ears are out of the way, but somewhat oversize. The rope hole is shorter than normal, so it may provide too much friction on stiff or muddy ropes. The eye is too narrow to accept two full size locking carabiners side by side, and its shape is not suitable for belaying.
Bob never told me what "TZ" stood for.