I owned one for the past couple of years, so it is not a 2.0. Just picked up a spare/second one at a ridiculous price; also not a 2.0.

So the first question is: What are the actual differences between a first gen. .45 Shield and the 2.0 version ?

Next question is: Is anyone aware of a parts compatibility list/chart between the various caliber Shields, even including the regular series M&P ? Hard to believe there aren't some parts that are compatible across the lines.

Finally: Other than a few parts, is seems very difficult to find spares with S&W's new policy concerning parts. By the same token, there must be some quiet sources. Not looking for major components, but the standard user-installed parts or assemblies.

Thanks for your patience reading this, and hopefully sharing. If you need to keep some/all of your information between us, rather than on the open forum, please PM or email me.

As far as I know, the original .45 Shield was the test bed for the 2.0 improvements.
Better stippling, trigger and forward serrations.
The older .45 Shields just don't say 2.0 on them.

Looks like Speed Shooter Specialties has closed shop, Midwest Gun Works is a good source for parts, also Brownell's

I'm not aware of a chart or list of cross compatible parts between Shields and the Full Size M&Ps, but surely there are some. The roll pins for sure !

__________________
U. S. Army Veteran

What sandog said. All Shield 45s are 2.0. After the 2.0 Shield 9 and 40 models were released, S&W started to stamp "2.0" on the 45's slides. To the best of my knowledge, that is the only difference between the original and the "2.0" Shield 45s.

Some of the very early Shield 45s suffered from failures to feed due to improperly designed magazine followers. S&W remedied this problem by shipping free redesigned followers to the affected Shield 45 owners. The failures to feed went away once the new followers were installed. In the very remote possibility that your newly acquired Shield still has the old followers, look at the right front of your followers. If they all have a vertical groove notched into the right front corner, you're good to go, because that's what the redesigned ones have. If there is no vertical groove, you've got the originals, so you should ask S&W customer service for free replacements.

Enjoy your new 45!

__________________
What, me worry?