Shelling peas by hand can be a slow process unless you have a long thumbnail that you can run up the pod to open it and strip the peas on the way back. This stainless-steel splitter has a small slitting hook at the base of a V-groove.
To use it, you slide the ring onto your index or middle finger and draw the pod through the groove to split it. The peas can then be stripped out. The splitter comes with an instruction sheet that tells you how to adjust the ring size and groove width if necessary.