Are Battery Terminal Posts All The Same Size ??

Mar 30, 2015
Lake Havasu City, Arizona
Do "marine" battery terminals accept the same post size as automotive batteries? Or are they different sizes? I want these type of battery terminals for my truck, but they state "marine terminals". I want to just go and get them. I can't find any close by like it.

(I don't want the cheap looking "strip & clamp" type, with the 2 bolts, because I have a nice copper eyelet soldered on the end of my negative cable). These will work perfectly if they fit the posts.

They say, "Special application marine terminals". What's so "special" about them?

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It looks to me that the marine part is referring to the two studs. All of the connects on my boat are ring connectors that require the stud to wingnut or nut onto. These would ideal for aboat where the battery only has the two posts, no studz.
So, these look as if they are designed to fit the small posts, not the standard large one's, correct?

(If you look at the hole size of the terminal, it looks very small compared to the threaded wing nut stud).
The answer to your title question is, no.
I had to shim a post on a neighbor's battery (G35) because the clamp wouldn't bite.
When I went to a 24F, no shimming was needed. Ergo, they can differ.
The only thing I've found with brass battery terminals, is if you have to close them up considerably to get them to fit tight, (depending on how large they're cast), it's best to heat them with a propane torch, then wrench them down to where they're almost a size for size fit.

Then allow them to air cool, (don't quench them), before you install them on the battery, and connect the wires. What this does is stress relieve the brass, and allow it to close up, without the risk of it cracking. I've seen cast brass battery terminals crack from being wrenched down too much. Brass is a lot harder than lead, and it is not as malleable.
I'm not sure the autozone version are the best most reliable connection money can buy.

I have these marine adapters on my RV and they work, they start a Ford 460, but they take a fair bit of maintenance-- dismantling, polishing, etc.

You'll want pliers to tighten those wing nuts a bit more than finger tight. Edit, the Amazon ones have normal nuts, better.

The ideal fix, sadly, is to get a premade cable, preferably OE.

And like said above, these aren't marine terminals because marine batteries have the studs built in. They're ghetto terminals so you can take an old car battery you have laying around and slap it in your boat.