D'Addario 9V Pigtail Pedal Power Adaptors - PW9VPC02
You're at the gig, and your adapter died. You scramble to put a battery in your pedal and OHHHHHHHHHH!!! in your haste, you ripped out the pigtail. Now What???
That's where the PW9VPC02 is a life saver! Plug in your 9v battery and plug the PW9VPC02 into your pedal. You finish the gig and GET PAID!
...talk about an inexpensive insurance policy.