Side channel blowers (pressure) or exhausters (vacuum) are used when a high flow (1200cm/hr) and up to -500 mbar vacuum are required. If you are comparing a unit you need to replace then the key numbers are the flow/ volume of air measured in CFM, m3/hr. To give an idea a good quality vacuum cleaner is similar in performance to a single stage 2.2kW side channel unit. The difference is that a side channel unit can operate for years. The other key characteristic is the vacuum level. If the flow and the vacuum level are similar then this is the correct unit. You can also check the motor size, dimensions and weight are similar.

They are available in two versions , a two stage unit (two fans inside) or a single stage unit (one fan inside). In general for a given motor size a single stage unit will give more airflow and less vacuum level (strength) than a 2 stage unit which which or a given motor size will give a stronger/deeper vacuum and less air flow.