Air conditioning relay issue
 

The issue is this: It appears to be discontinued.

I discovered my relay was bad and it is the same as the horn relay so I swapped them and everything's fine with the AC and I have no horn. But I'm confused because all the relays look the same. What makes the horn and AC relays special.

I ask because a ton of relays on amazon will physically fit, but I also noticed the schematic says the AC one is a 50 amp relay, but few relays I've seen at any site give the amperage.

Anybody have thoughts on this?