AMX Teknology Shearwater Petrel Aluminum Protective CaseShearwater Petrel Aluminum Protective Case Case will fit both stand alone and wired versions of the Shearwater Petrel 2 and the NEW Shearwater Petrel 3! The new PETREL Generation 2 and 3 Titanium Protector has been developed to improve the protection of your Shearwater dive computer. This new design does not require any removal of the porthole screws. It simply covers the case over almost 10 mm. the side protection is improved and the hold in position