- Design variants: version 1 (impeller on the motor shaft); - Fans are certified: compliance with the requirements of TR EAEC 043/2017 and GOST R 53302-2009; - Purpose: smoke ventilation systems; - Impellers of 3 types of execution: RV6, RV6k, RV9; - Structural design of impeller blades: bent backwards; - Housing design: spiral rotary single-sided suction; - Used index in the abbreviated designation for smoke exhaust systems: DU; - Possible fire resistance versions: 400°C / 2 hours and 600°C / 1.5 hours.