The 304 and 316 high-strength version quick links are made with a slightly larger nut adding better holding power.
The 304 SS and 316 SS 7mm and 8mm quick links have stamped ratings from the manufacturer.
Climbing Taiwan’s break test videos & results:
8 mm 316 SS Zoutianya: 55.86 kN (test terminated), 69.14 kN, 48.79 kN Video
8 mm 316 SS Climbing Taiwan: Rated Breaking Strength 30 kN
8 mm 304 SS (high-strength) Ningjing : 68.66 kN Video
7 mm 304 SS Barhar : 52.80 kN, 52.95 kN Video Video
7 mm 304 SS (high-strength) Ningjing : 51.27 kN, 46.50 kN, 50.61 kN Video
CTW 6mm 316 stainless steel high-strength long quick link, 22 kN
The 304 SS & 316 SS of both 7mm & 8mm long quick links have stamped ratings from the manufacturer.