Have not seen a ratcheting wrench in stainless or aluminium, but I would love one too!

The nacra infusion assembly manual does not say it is a 17mm head, but it does say a 17mm spanner is required for assembly with no other sizes specified.

Found getting the diamonds up to the heavy weather setting to get pretty stiff. May be pretty difficult to do on the water with the boat bouncing around.

C2 AUS 222 by Goodall design
"Darph Bobo"