The Knack was a TTO, while these are three-piece razors.
You could say the Knack was a Tech in the same sense that the Ranger Tech was a Tech technically speaking. By that standard all the Gillettes after about 1940 were Techs. But in common usage "Tech" usually means a three-piece razor.
Arf. You're right. But it depends what's your reference !
Mr-Razor classify the Knack as Gillette Tech. (it's one of my favorite site shaving reference website)
I like "Tech" and I find sometimes difficult to identify them.