My 10 year old Murray tractor came with a pigtail, a short piece (3") of
electrical wire with spade plugs on each end.
I never used it and don't know why they included it.

I think some of the older Murrays have the mower clutch
switch mounted on the mower deck, so you need to be
able to jumper the deck connection if you want to run
without the deck mounted. Their newer ones changed
that so the clutch handle (and its switch) stayed on the
tractor...

--Glenn Lyford