Description Although designed to help with wider high cap magazines, there is also a groove inside the mag well, front and rear, to align a 1911 style magazine. Years later and more innovations came along we expanded to a complete line as we offer now. If it is not and ADCO, it’s not a Super Thumb. The one that guaranteed not to break. ST1  21.5mm x 32.5mm  • 1-1/4” x 13/16” Most Double-Stack Magazines 92, 111G2, G2c, G3, G3c, G3X, GX4, 1911 Specifications: Inside capacity: 21.5mmx32.5mm (0.88″x1.25″) Fits the following handguns: Beretta 92-96, Cougar 8000 and ’40 Browning High Power CZ 75 Kel-Tec 9 or 40 S&W 59, 99 and 4000 SIG P226 and P228 Taurus 92 and 111