The LA-DC58L Conversion Lens Adapter for PowerShot G15 & G16 Digital Cameras from Canon screws
onto the face of the Canon G15 or G16 around the lens and is required
in order to attach optional converter lenses and accessories to the
camera. Without accessories attached, it can also be used to provide
protection for the lens from accidental impact. Accessories including
the TC-DC58E Tele-Converter, the MP-14EX Macro Ring Lite and the MT-24EX
Macro Twin Lite connect to this all metal conversion adapter.