'The one without the spring'? MagGuts IS the spring.
The original MagGuts had a 2-Piece spring setup and accommodated 1 additional round. The V2 has a 'Z' spring that adds 1 additional round when used with the standard base plate and 2 additional rounds if using the extended base plate.
I have both styles and both work just fine in my Shield. Looking at the website, it looks as though they no longer offer the original 2-Piece spring version.
Smith & Wesson Shield 9mm MagGuts™-High Capacity Magazine Conversion (+1) Adds a round to your S&W Shield 9mm magazine without extension. The conversion uses your existing magazine tube and base plate while replacing all internal components with the MagGuts™ ZeeSpring™ spring and follower...
I have them in all my 7 rnd mags to make 8 +1. Never had it hang up or jam up in 1000+ rnds. I used the springs from magguts and then added the ndz base plate pinky ext. Although it will be going in the safe. Just upgraded to the shield plus last month. Just get the springs you wont be disappointed. They are really tight at first and you will need to break in the springs. Good luck and happy shooting.
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