Cressi Purge Button Cover for XS-Compact II Stage and Octopus | Official Spare Parts Colored Purge Button for the Cressi XS-Compact 2nd stage. This is an official Cressi replacement for Cressi regulators. The Purge Button is made of long-lasting rubber and can be installed easily by the end user. The product is made by Cressi, a brand pioneer in Scuba Diving, Snorkeling and Swimming equipment.