The laminations are realized by metal stamping process from cold rolled strip with thickness from 0.10 to 0.5 mm, depending on the types, previously isolated or not.
After stamping, the laminations undergo the final heat treatment appropriate to the used alloy. 

They can be supplied in the following alloys:
- Nickel iron 50%
- Nickel iron 80%
- Cobalt iron 

The most common shapes are designated as follows:E, ED, EE, EJ, L, M, U, et W.