I know they are TIR optics and I’ve bought some from FastTech and others in the past, but none seem to be like the optics LL used and none throw they same.
It throws better than a reflector the same size, but you might be a bit disappointed if you're expecting a laser tight beam or something.
Also, it reduces the spill, but not completely. The spill probably ends up being 30-45 degrees wide depending on how you define the cutoff. It's hard to measure because the edges fade away instead of cutting off suddenly.
I have the Carclo 20mm 10003 & 26mm 10048, both have that nasty square die image artifact even using unmodified holders (so it's not that I screwed up the focus), I won't even consider using them in anything. The IOS 10* is beautiful. Small spot with a very sharp edge, nice even corona with a very soft edge, and very little outer spill.
Oooh, yeah, I should have mentioned that. I hope I didn't give the wrong impression.
I used the Carclo image as an example of the general proportion of the spill compared to the hotspot. I didn't mean to suggest that the IOS PMMA optic had that square die projection that Carclo polycarb optics are known for. Sorry, I should have been clearer about that.
Don't know, but most of them on the 'cheap' sites either have no holder, or are made to fit the old 1W/3W LEDs. I'd be shocked if any of them matched what that 10* can do.
Oh no, I wasn't correcting you, just adding more info. :)