Is this a safety spool or a jump spool? At a glance, what does it look like to you?
Those things are different things. They might look the same. They might sound the same. They both have "spool" in their name. But they aren't the same thing.
A safety spool is a safety spool.
A jump spool is a jump spool.
And it confuses me about how much it causes people to look confused when I tell them this.
"I have 2 jump spools."
"No you don't."
"Yes. I have two spools."
"How many jumps are we going to make?"
"So you don't have any jump spools. You have safety spools."
Safety spools are there for unpredictable just-in-caseness. You should ALWAYS have at least one (two are better) on you.
Jump spools are for planned navigation. You should be carrying, as a team, as many are required for your dive plan.
A spool is a spool is a spool the same way that a knife is a knife is a knife.
You gonna use a butter knife to cut an Amazon package open?
You gonna use a butterfly knife to spread butter?
You gonna use a foot-long bowie-knife to chop onions for dinner?
A spool is called the same thing. But it doesn't served the same function.