The kit comes with a new, longer spring, the two piece extension housing, 5 screws (in case you lose one?) an allen wrench and instructions.
You have to reuse you floor plate.
Per the Instructions, when installing you want to file the bottom inside edge of your P-mag to help guide the follower.
When installing be careful not to over-tighten the screws as you could crack the plastic.
I didn't have any black P-mags and these only come in black, clear and pink. So I decided to paint it to match my Flat Dark Earth P-mag and furniture.
I did some online research and discovered that the only spray paint known to match Magpul's FDE color is Brownell's Aluma Hyde II in Coyote tan.
you can find it here
DuraCoat also makes a color designed to match but neither of these options were cheap and quick.
So I had some Krylon Fusion in Khaki, which is close but a shade or two lighter.
After installing the kit, I set it outside for painting
Here it is finished
And next to an original FDE P-mag for size and color comparison
I was at Wally-Mart getting some sundries and decided to check out the paint section just to see if they had any "dirt brown" colors that might match the Flat Dark Earth.
I came across this color from Rustoleum, called "nutmeg" and decided to give it a try.
I lightly misted the magazine, you can see the color is darker, but still not green enough to match, but this is close enough. I think I will add this color to my camo colors when painting camo patterns, it is right in between the chocolate brown & khaki
I'll have to update this after I try the magazine out. I have been told that they are reliable, but you should avoid dropping them on the ground, the plastic is more brittle than the material the P-Mags are made with and could crack.