ISO 1127, ISO 2037, ISO 2852
ISO European Tri-Clamp Standard is available in 3 different dimensional standards, to suit compatible tube standards.
ISO 1127 Series 1
ISO 2852 standard was replaced by ISO 2037 in 1982, In turn ISO 2037 standard was then replaced by ISO 1127 in 1996
The more comprehsive ISO 1127 standard was introduced to harmonize the ISO2037 & ISO2852 standards,falling into line with ISO tube sizes available.