How to select right heating element for Dražice water heater

The assembly option of built-in electric units with flanges ranges R, SE

▲ Can be fitted
■ Can only be fitted with the 225/150 reduction flange 
● Can only be fitted with the 210/150 reduction flange
-  Cannot be fitted

Assembly option of individual TPK units

▲ Can be fitted
■ Can only be fitted with the 225/210 reduction flange
-  Cannot be fitted

Assembly option of individual TJ 6/4" units

* TJ 6/4" with extended cold part
▲ Can be fitted
-  Cannot be fitted