A Canadian vessel needs Transport Canada approved flares to be legal. Same issue as we have with life jackets.
I emailed Orion and asked them if there was any difference between the flares they sold with USCG certification and those with Transport Canada certification. Here is what their rep had to say.
Canadian Coast Guard regulations are different than United States.
US expiration is 42 months from manufacture
CA expiration is 48 months from manufacture
The manufacturing process is the same.
I then went back to clarify that aside from the printing, the flares were identical and was advised:
On, most products they are identical. However, on the 12 gauge and the Skyblazer XLT, the Canadian Coast Guard require a twin star, whereas the US only requires one star.