I was out in the woods of New England with a friend on our electric mountain bikes. I realized my friend was no longer behind me so I went back to find him. He had is chain in his hand as it had snapped. I had a pair of the links in my backpack along with a chain breaker and link pliers, within 10 minutes we were back on the trail without having to push his bike around 2 miles back to the road! I will never ride without them in my pack!!
I have been using the 12 speed missing link on my Campagnolo 12 speed groupset for over a year with no problems. Works great