Bracket in Grumman Canoe

I just got a 17’ Grumman Standard. On the deck (floor) there are two flat brackets fixed to the floor, one far aft and the other just forward of the rear seat. Does anyone know what they are and/or used for?

Maybe some sort o’
sail step or sailin’ gizmo thang?


It is for a Grumman sail rig kit (NM)

Correct - Mast mount
After googling sailing kit I find you are correct. It is where the mast mount is attached for the sailing kit. And I was incorrect about the location. They are fore and aft of the front seat.