Heating radiators with side connection

Side

— radiators with connection holes located on the side — usually directly opposite the top and bottom tubes, so that the distance between these holes corresponds to the centre distance (see the relevant paragraph). In most of these models, holes are provided on both sides, which allows the use of both one-sided and through supply of coolant (including at different levels); however, for a full guarantee, this nuance needs to be specified separately.

Also note that this option is standard for sectional and tubular radiators (see "Type"), although it is very popular in other varieties.