Hard Line tube OD standard changed?
So I have not done a new systems / upgrade in more then a few years and I have come back to find that the fitting makers no longer follow standard tube OD's from what i can find. E.g they look to no longer make fittings for 1/2" 12.7mm(use to be sold as 13mm in some places) but instead 7/16" 12mm, 9/16" 14mm.
Now the issue i have here is that 7/16" 12mm and 9/16" 14mm step away from standard tube OD's used and there for i can not used standard 1/2" tube or other standard tube OD's. If I am wrong here and in fact i can use 12.7mm 1/2" OD copper tube with these 12mm 7/16" OD fittings then i will leave it at that but if this is not the case, then i feel what they have done is kind of dum and them trying to be special snowflakes for no reason imo.
Thank you in advance for any information regarding this.