The product information / comparison is always in the context of a concrete application.
Please select your relevant application:

Measuring task	Product name
Density	Densitycontroller, Liquiphant FML621	Liquiphant M FTL50H	Liquiphant M FTL51	Liquiphant M FTL50	Liquiphant M FTL51C	Liquiphant M FTL51H
Point Level / Liquids	Liquiphant M FTL50H	Liquiphant M FTL51	Liquiphant M FTL50	Liquiphant M FTL51C	Liquiphant M FTL51H