The polymer lock plate should be used with the polymer base. The metal one doesn't begin to have the protrusion needed to keep the base plate on. It barely works with metal to metal on the P380. The base comes off too easily., especially if you drop your pistol as I have. The base is easily thumbed off the P380 mags and you're asking for problems if you try to be cheap by using the metal base locking plate.
I don't like the "flush-fitting" polymer bases for CC and got metal ones for my P40, but had to add an O-ring because the gap was big enough in front to "bite" my pinky finger!
I used neoprene plumbers O-rings... 3/32" thick and 3/4" inner diameter. 1/8" was too thick and 15/16" I.D. was too loose and caused binding or too much pressure on the magazine catch.
Wynn
When you're buying base plates search for the base plate kit and save a few bucks over buying separate bases and lock plates:
When you get where you can look up a part, enter "base plate kit" and look for your caliber, or try adding that to the search as well, but the "kit" is $15.50 versus $8.80 each for the two parts, saving $2.10.
USAF Retired '88, NRA Life Member. Wife USAF Retired '96
Avatar: Wynn re-enlists his wife Desiree, circa 1988 Loring AFB, ME. 42nd BMW, Heavy (SAC) B-52G's
Frédéric Bastiat’s essay, The Law: http://mises.org/books/thelaw.pdf
Thomas Jefferson said
“A government big enough to give you everything you want, is strong enough to take everything you have.”
and
"Peace is that brief glorious moment in history when everybody stands around reloading".