Three-dimensional nonlinear eddy current and stray-field loss analysis of multisteel configurations based on TEAM Problem 21 family and the related validation are presented. Some extended investigations to Problem 21, referred to as postbenchmarking, are outlined. The newly measured and calculated results of both the magnetic field and the stray-field loss illustrate the electromagnetic behavior of the prototype model. It is indicated that the power loss distribution in the multisteel parts closely depends on the material configuration and the applied fields.