Dear p’ Montree krub
Highly appreciate for your worthy reply below and ref STD change to EN74 as update (BS1139 had been obsoleted )
One more thing that you info for Yellow color are type/grade “C” quite low quality and low performance property to use such as sensitive to crack rather than grade “A”
So please kindly educate me how we can see/know what different of each grade from return to shore, or at least shade color
Thank you in advance to reply