PETZL MAILLON RAPIDE QUICKLINK

Don't let the picture fool you - This thing is pretty big. Can run 1/2" Hi-Vee through it and have just a little bit of room on each side of the rope. Actual dimensions are 4.25" tall x 1.75" wide. 0.75" width inside the link ends. Just under 7/8" gate opening (21mm) when fully open - Gate turns smooth as butter. Looks to be Galvanized/Zinc coated. Comparable to a 4th gen iPod Nano, but ~0.5" taller and about 2-3 times thicker. 4/5 because mine came with a pretty big forging flaw/divot on it under the zinc coating.

Good solid quick link for the money! Gate opening is 1/2". Screw gate operates very smooth. Good quality!