Let me start by saying, these FIGODE chain locks are no joke. I've been using them to secure my electric bike outside my apartment in a not-so-great neighborhood, and they've held up like champs.
The stainless steel construction feels incredibly sturdy - you can immediately tell this isn't some flimsy dollar store lock. The 7.25mm diameter chain has some serious weight to it, and the luminous nylon covering is a nice touch for nighttime visibility.
What really impressed me was the marine-grade 304 stainless steel. I took one of the locks on my friend's boat as a test (with his permission, of course), and after weeks of saltwater exposure, it showed zero signs of rust or corrosion.
The locking mechanism is simple but effective - just a 90-degree turn to open/close. The snake-shaped keyway is clever too; I tried jamming random objects in there out of curiosity, and nothing could trip it open.
Now for the downsides: While most units seem fine, there have been reports (including one in the reviews) of defective locks that don't actually secure properly. Also at $60 for two, they're not exactly cheap - though you do get six keys total.
Pro tip: These work great as primary or secondary locks. I use one on my bike's frame and another looping through the wheels - would take some determined thieves with serious tools to get through both.