The 445 diode operates with a interesting lower bound of operation. At low powers the 445 diode becomes extremely unstable, fluctuating on and off, as it is JUST barely turning it on. Using the 1W 445 diodes commonly manufactured, there is a far greater margin of error that exists here. It needs to be run I'd say for 100 more milliwatts than its anticipated lasing threshold.
just read this. i'm researching how to build a rgb with a 445 instead of 405. the 445 would have to be low power in relation to 635 & 532. if the Nichia diodes can only operate around ½-1½W, perhaps there's another diode that uses lower specs. i assumed the Nichia was high powered because it's designed for projector equipment.
Most of the people in this thread have the wrong ideas.
These pens most likely aren't the multimode projector 445 diodes we're used to, they most likely use the new 50mW single mode 3.8mm 450nm osram, etc, diodes that are available now. The price is about in line with using those diodes and they are touted to be 450nm instead of 445.
It's a good buy for wavelength collectors. but the 'burning' crowd likely won't have much interest in these.