They are. Same shell, just black.

This is published by Alliant, and may be the only load you ever need. I use the same thing with Fiocchi primers, but I can't advise you to do that. You didn't hear it here.

Shotshell
12 Gauge 2 3/4-in. Remington Plastic Shells (STS, Nitro 27, Premier RXP and Gun Club)
1 oz. shot wt.
Rem 209P
CB 1100-12
16.5 grains Red Dot (or Promo)
7,400 psi

"The price of good shotgunnery is constant practice" - Fred Kimble