Hultafors - Rafter Square - Hip-Val 

0.6 M = 6 DM = 60 CM = 600mm

Dude, on the long side of the triangle you have the angle scale. So if your plan includes both different angles then you just mark those angles How hard is it to watch the damn video in which he even first shows the angle scale?

It's a Hultafors Dry Marker: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-230fioTm3Xg.html

cm is in 100, inches 12, that is why.

There are different brands of metric speed squares, and some are "kind of metric", like Milwaukee square I bought. Take a look at common cut number corresponding to 45 degrees. In this video, you read 10 dm / 1m = 1m/1m and it is truly metric. On Milwaukee square I have it is 12, which proofs it is not metric, instead denoted in inches per foot. 12" = 1ft = 1:1 ratio, thus 45 degrees. Maybe this answer helps some confused carpenter's souls ;)

rise and run works off a base of 1 metre like tan cos ect

A good video and very well explained! But when we are working in metric the pitch of the roofs and the measurements on the drawings are in metric and degrees, surely it’s best to calculate in metric and degrees and definitely not decimetres!

@@chrisdaniels6899 rise and run doesn’t need sohcahtoa

good question. i guess you go aproximately