stainless steel or standard nut

[GEORGE D.]

what do you guys use on your boat batteries terminals thanks for your help george

[ash]

Standard Nut - has always been good for me and occasionally check for tightness between trips - especially after a bumpy day.

[Turkeyman]

Standard wing nut with battery terminal grease to prevent corrosion of cable terminals.

[Dave Wilson]

All 4 of my batteries came with SS wing nuts, so that is what I use.

[DanIsaac]

SS nut usually 9/16 with a SS lock washer.

[bryanmc]

Stainless nyloc over a stainless flat washed

[WRB]

Washers give you more contact surface area and prevent terminal twisting when tighning.
I use SST wing nuts with SST flat for 2 reasons, to prevent over torqing and breaking the battery post and ease of removing with pliers in lieu of finding a wrench, always have pliers handy.
9/16 hex nut for 5/16 stud, 5/8 ffor 3/8 stud, it depends on the battery stud size, wing nuts it doesn't matter.
Tom