Must be a hell of a chain. If 25 ft. costs $633 you'd have to be looking at 3/4", which, if it's grade 100 is rated at 35,000+ lbs and weighs over 150 lbs for 25 ft. of it.As tractors got bigger on the farm,, we ended up lengthening a couple chains, to the point that they would no longer bend,,
At that point, my BIL went to Richmond VA (in 1973) and bought two chains that are 25 feet long, and cost $100 each.
They still use the two chains, and they are as good as the day they were purchased..
I checked the inflation, from then, to now,, those chains cost $633 each, in todays dollars.
I guess that is why they still survive,, even though the horsepower has grown on the farm, considerably.