Pink looks nice. Note that this hub is for Campagnolo, hence no spacer. You can use this on 9, 10, and 11 speed Campagnolo.
The classic red hub. This is for Shimano/SRAM - note the spacer. This hub can be used for S/S 8, 9, and 10 with the spacer, and 11 speed without it. The rubber band is just to keep the spacer on during handling and shipment - always remove it.
We include spacers with every 11 speed S/S hub we sell. If you have a Shimano cassette that comes with a spacer, consider that spacer to be a part of the cassette no matter which hub you are using. Always use it.