Question on Wilson case length gages

[RM]

I see that L.E. Wilson sells both "case length gages" and "Max cartridge gages" for the various handgun calibers. What's the difference? Thank you.

 

[Bullet]

From Wilson’s site -

http://lewilson.com/products.html

Case Gage -

One piece gage that will check overall length to indicate the need for trimming, datum to head length to assure correct headspace and to prevent over sizing.


Case Length Gage -

One-piece, non adjustable cylinder-type gage with milled surfaces on one end for checking minimum and maximum overall length of rifle and pistol cases having no shoulder

Looks like one is for cases with a shoulder the other for cases with no shoulder.

Wilson also makes -

Adjustable Case Gage -

For belted mags. While the belt provides support for proper headspace, the life of the case will drastically shorten unless resizing is held to a minimum at the shoulder. These gages, which can be adjusted to be used with individual rifles of the same caliber, will enable the handloader to control the amount of resizing simply by measuring a fired case. Overall length can also be checked with these gages.

Pistol Max Gage -

The Pistol Max Gage measures the maximum dimensions of a loaded round.