All the products in this category have the external thread in size 1 1/4" BSP (i.e. DN32).
The category gathers the PHE models from the serie Ba-27 and some models from the series Ba-60. These can be both relatively small units with 0.54m² of surface (like the PHE Ba-27-20) and bigger units, predestinated mostly for Heat Pumps with the plate surface bigger then 3,6m².
These are heat exchangers that potentially maintain less resistance to flows, which is particularly important in more extensive or larger central heating installations.