15mm / 19mm dovetail....???

[DDirector]

I am purchasing the tilta dovetail shoulder mount. But I see two different versions.
One for 15mm and the other for 19mm dovetails.
I'm so confused. What does this mean?
It looks identical and costs the same. Even on eBay I see people saying to state which one I have. But other times they say it's compatible with both.

19mm:
http://ikancorp.com/mobile/productdetail.php?id=701

15mm:
http://ikancorp.com/mobile/productdetail.php?id=773

 

[indiawilds]

In 19mm the dovetail is Arri standard. In 15mm, it is not Arri standard dovetail. So if you have a Arri standard dovetail for your tripod and using a bridgeplate then the same is going to work with the 19mm Arri style handheld rig ie. easily shift between the two.

Better to standardise everything to one standard either 15mm or 19mm.

 

[DDirector]

Hmm.. okay.
Can you help me wit this then?

I am purchasing the Tilta C300 rig. Which is not the standard dovetail .
http://ikancorp.com/productdetail.php?id=698

I need the dovetail shoulder mount for this. So, the 15mm is the choice for me then.
BUT, what if I will be mounting a 19mm bridgetplate to the bottom of the cage system that has/accepts the standard arri dovetail?
http://ikancorp.com/productdetail.php?id=713

Will the non-standard (15mm) dovetail shoulder mount work with both the standard and non-standard dovetails?
What about the arri standard (19mm) shoulder mount?

I'm not sure whether Ill be using 15mm LW or 19mm studio now. But, in the future I'll be using both.
So, which shoulder mount system should I be buying?