From ebm-papst, these DC Compact Fan Kits are a quick and efficient way to address ventilation needs. The fan kits incorporate a range of DC fans, and are supplied with a power lead and speed controller as standard. Each kit will also include either a finger guard or an air filter, see below.

Part numbers ending with "KR0" include a wire guard.
Part numbers ending with "KR1" include an air filter.

These 12 and 24 Vdc fans are protected to IP20, and can operate at either 50 or 60Hz. The filer pads for these units can be changed without switching off the fan.
12 & 24 Vdc fans
Plastic fan housings
IP20 Protection
Lead 310mm
Filter pads that can be changed without switching off the fan