The IKO IRT4525 is an inner ring in the IKO Inner Rings product series. It is listed for shell-type assembly and is made of high carbon chrome steel.
The supplied product data lists the following metric dimensions for the IRT4525:
The product data identifies the TA 5025Z under assembled bearings for the TA_Z, TAM group and TLA 5025Z under the TLA_Z, TLAM group. No assembled bearing is listed for the YT, YTL group. The detail description also states that the ring is to assemble with TA5025Z and TLA5025Z.