CNMG120404/08/12 CQ 4609 Chipbreaker insert steel grade of Tabikut pack of 10 high quality screw 4 mm There are many Chinese brands

There are many Chinese brands also making the same inserts so you can just check the description of the size from other brands to fix this insert

5μmUsed for Face Mill

Insert it into this

The internal cam removes the collet when unscrewedMARSTECH CODE IS ER25UM TYPE NUT

Made of special steel for higher rigidity properly heat-treated

CNMG120404/08/12 CQ 4609 Chipbreaker insert steel grade of Tabikut pack of 10 high quality screw 4 mm There are many Chinese brandsCNMG120404 08 12 CQ4609 Carbide Insert with 0. 8 mm Radius used on Steel, Mild Steel General Parameters are mentioned in the box One box contains 10 inserts. This is a steel grade, not cast iron.