Part Application Help

[tremor]

So I just took inventory of the parts my dad had on hand for our 02 JD Sabre, 42" deck with a 17.5 Kolher engine.
I found a new belt with the part number M124892, and I can't figure out what it's for. All my father had done was write 'Sabre' on the cardboard sleeve.
Any help in figuring out what this belt is for? I did a Google search, and came up with nothing.
(Can't ask my dad btw)

 

[BBO]

I think the number should be M124895.

 

[tremor]

Drive belt. Thanks for pointing me in thr right direction.