IWC set of 4 upper and lower incabloc cal. 852 853

IWC 852 853 incabloc ( set of 4 pieces )
I don't know which incabloc is for which caliber, the 4 incablocs were in the same tube written 852 - 853

2 incablocs looks to be upper , 2 differents sizes : 2.86 mm and 2.72 mm. Maybe one is for 852 and the other for 853
1 incabloc has a diameter of 2.30 mm , I don't know for which caliber it is
1 incabloc looks to be lower, diameter is 3.19 mm