Ancilliary Packs for Cased and Contra-Rotating Axial Fans. The SPANC Ancillary pack range is a complete kit of matched parts selected to isolate axial fans from the surrounding structure. The SPANC Pack consists of: 2x Matching Flanges 2x Flexible Connectors 4x Flexible Connection Bands 2x Universal Mounting Feet 4x Anti-Vibration Mounts The components are selected to isolate Cased and Contra-Rotating Axial Fans and are standardized for units of 250mm diameter.