This is a Garmin GAP-26 pitot mount install bracket.
This works with all GAP-26 models.
Garmin part number: 011-03609-00
According to the manual you will need #6-32 and #8-32 screws (not included).
“Screws of appropriate length for the specific installation shall be used to fasten the GAP 26adjustable mount to the inspection panel (or combination panel and doubler). Required screw sizeis #8-32.”
“#6-32 screws (4 pcs), required length (.218” min – .312” max), recommend screws with nylon patch on threads for thread locking for mounting probe.”
“#4 or #6 (4 pcs) pan or hex head screws for mounting heater control box.”