Data sheet calls for 2.5 mm screws but you can use ASE 4-40 screws and tap. They are pretty much the same size and easier to find here in the states. I use PK3 for thermal compound Artic silver 5 is also a good one. PK3 is the better of the two though.
. I use these on vero 10's and vero 18's. 
I used oil. Drilled thru so wasn't a blind hole. Should have gotten shorter screws.. I got ancy and tried to do one without backing it out and cleaning tap and snapped it when i went to back it out. Obv peice of aluminum caught thread. My fault. Was just taking too long as had 30 holes to tap. Self tappers were so much faster. I even used drill with screwdriver bit. Went in a bit then back out just like tapping. Then cleaned holes and used new screws.
Yeah I've had only one other but i saw more at this liquor store I usually do t go too I'm gonna pick up some ones I've tried yet and see how they are. That one in my avatar is my favorite beer right now, you live in Ak?
Damn but they look really good dude the plants, and your light is sweet, I'm gonna pick up so, CXBs soon and make a flower panel. The verso will be for vegging, I'm curious about the new veros coming out soon.
Is pk-3 not any good I just ordered some today?
Ya, the cobs clearly work. My first grow so still learning.
It works im sure, read all the reviews for computers. Im sure it will be fine. I just dont like it for cobs but most people do. I found it too thick to work with so removed most and left a thin layer...good enough. For me the adhesive worked better and no need to drill and tap holes so a huge time saver. As far as thermal properties I have no idea if one is better than the other but again feel the adhesive is good enough. Would have taken 10-20 minutes to install with adhesive vs hours I spent sanding heatsink, drilling, tapping, screwing, applying PK3, then I didnt like how it went on so redid it all...just was a PITA.
