Yes- Flex-watt is also placed OUTSIDE, underneath the tank. And the probe is sandwiched between the glass & the UTH, then the t-stat adjusted when the INSIDE temp. is correct as measured directly over the bare glass, without substrate (as could happen when snakes get pushy & burrow down).
That product from reptile-basics is not "Flex-watt" brand but is made similar- I cannot speak for that which I've never tried. I think you can get the brand Flex-watt from "The Bean Farm" (online), if you wish. But do be advised (at least in my experience- & mine is all old "original" Flex-watt) that Flex-watt doesn't get quite as hot as some other UTH -like the one you had that tried a meltdown.
The kinds of snakes I keep (not BPs currently) do not require as much heat as BPs do either, so I prefer Flex-watt. I've had nothing but long-term (decades!) of safe operation using it. Safety when using any UTH depends on controlling it correctly- with a t-stat (or rheostat, where applicable). That generally prevents problems, as does correct installation- leaving the small air-gap as directed, & don't let a tank or enclosure sit directly on a wire- as over time, that can cause a failure too. And don't over-insulate OVER any UTH with deep substrate.
Yeah, I wondered why you stopped talking to us?

Welcome back...