This Part 1 of the standard specifies the dimensions, with their associated tolerances, of a range of laminated core packages using YEE 2 laminations,both in their standard configuration and for assemblies using two larger E parts. NOTE - Laminated cores are normally constructed from laminations made from material of the composition corresponding to the designation C22, El, E3, E4 or F1 (see Table I of IEC Publication 740).