The KRKW / RSKW non-return damper has a tight design according to the ÖN M 6027 standard. The KRKW / RSKW damper blade consists of a frame and of a silicone membrane. The KRKW/ RSKW tight non-return damper is suitable for vertical or horizontal installation. The installation is done by inserting the damper into a duct. The non-return damper has a double-lipped seal for sealing and fixing in the duct.

The KPK odour-resistant non-return dampers are equipped with a permanent magnet, which ensures the closing of the tight damper when pressure drops. The closing and opening pressure of the damper can be adjusted with a screw. The design of the KPK tight non-return dampers allows a direct insertion into a ventilation duct. The non-return dampers are suitable for kitchen hoods.

The RSK non-return dampers are designed for circular ducts. The RSK backdraught dampers have the "butterfly" design and are made of galvanized steel. Installation of RSK non-return dampers is only possible with the axle vertically in a horizontal duct.

The RSKT tight non-return dampers are designed for installation in circular ducts. The airtight inserting "butterfly" non-return dampers are made of galvanized steel, the blade and the connection sockets are provided with seals.

The MCA is a non-return damper for use in conjunction with the MAR, MBR and KTB adapter to create the MIXVENT-TWIN combination. The MCA non-return dampers are made of metal, varnished in the same colour as the TD Mixvent fans. The MCA dampers are mounted directly to the TD Mixvent fans, including seals as direct accessory. The non-return damper blades are made of aluminium.

VS are negative pressure non-return dampers designed to prevent backflow of air into the ventilated space. They open automatically under negative pressure when the fan is started. The lightweight damper wings are made of thin aluminium sheet. The underpressure dampers have a flange made of galvanized sheet metal. They are mounted from below with screws in the prepared threads, directly on the fan base plate. The VS non-return dampers are designed for use with NK and NDH roof attachments. The pressure drop characteristics of the VS dampers are shown in the charts.

The JCA backdraft gravity dampers are designed for roof fans. The JCA backdraft gravity dampers for TH, CTH, CTV and HCT roof fans are made of galvanized sheet steel.

The LRK(F) non-return dampers are designed for installation in circular ducts in vertical and horizontal position. The dampers can withstand a maximum temperature of up to 400 °C for two hours. The LRK(F) dampers are made of galvanized sheet steel.

The NKTM pressure relief non-return dampers are used for automatic closing of HVAC ducts in case of fan shutdown. The NKTM pressure relief non-return dampers are designed either without rod (design .01) or with rod (design .01T). The NKTM non-return dampers prevent backflow of air in case of shutdown of a fan. The maximum flow speed is 12 m / s and the maximum overpressure in the damper is 1500 Pa.

The NKTM non-return dampers are designed for installation in HVAC ducting or for installation at its end. The pressure relief damper is designed for installation in vertical or horizontal ducts. If installed in horizontal ducts, the axis of damper blades must be horizontal. Damper bodies and blades are made of galvanized sheet metal without further surface treatment. Plain bearings are made of durable flame retardant nylon.

The VKS-P non-return dampers are recommended accessories for the PRF / PRF-Ex acid-proof fans. The dampers are made of PP. The VKS-P dampers must not be placed in a vertical duct with the air flow downwards.

BDS are butterfly non-return dampers designed as accessories for SMG, SV, SUSB, SVB, SMF, SMG, SUA HR and HRV ventilation grilles. Installation of slide-in backdraft shutters is done by inserting them into the socket of the ventilation grille of the corresponding diameter.