The T2 and F75 share the same mechanical package. The T2 was the first metal detector in history to be designed from the ground up scientifically according to ergonomic principles. That's why the T2 and F75 are the only metal detectors in the industry for which the manufacturer actually publishes the ergonomic specifications. The other manufacturers literally don't know how, and wouldn't dare to publish if they did know how, because after all look what they're shipping to customers!
Weight matters, but It's not all about weight. The T2/F75 comes in at around 3 1/2 pounds (1.6 kg) with batteries. There are machines out there that weigh less, but very few that put less wear and tear on the human body even though they may weigh much less. On the other end of the stick (not just figuratively speaking), a mere 3 pounds can be like swinging an anvil on the end of a broomstick. I won't mention a brand name, but for some of y'all, a particular brand will immediately come to mind.
This is a good moment to give a nod to some engineers from 30 years ago: Dick Williams, Carol Chandler, and Marvin Jones (Mr. Jones still being with the company). They designed the 1260-X mechanical package before they even knew what electronics were going to go in the box, and I was the guy whom Jim Lewellyn hired to stick some electronics in it. The rest is history. The 1260-X mechanical package was not designed scientifically, but a lot of seat-of-the-pants intuition went into it. It was 4 pounds, not bad for that era, and in its day nothing matched it for ergonomics. I spent years studying that mechanical package trying to understand what made it so right. And that's why old-timers see in the T2 and F75 a legacy that goes back to the revolutionary 1260-X, the grandfather not only of the T2/F75 mechanical package, but of all second derivative motion discriminators (which includes the overwhelming majority of discriminators on the market today).
--Dave J.