Campagnolo HB-BO023 USB ceramic front bearings.
The picture shows a pair of bearings in a bag. The price however is for one bearing ring. If you want a pair of bearing rings buy two.
These fit any front hub from 2015 with USB or the CULT bearing system using the 14mm axle. Theh also fit hub with he same axle that have the standard steel bearings such as the zonda wheel I.e an upgrade.
Please check the campagnolo spare parts diagram to ensure your buying the correct parts.