Each MIDI Sprout comes with three pairs of electrode pads and one pair of electrode leads (wires). The pads are reusable and can last months or years. In fact, we've been using the same pads over at Plants FM for about 8 months now and they're doing great!
While the pads for your MIDI Sprout are reusable, they may get dirty or begin to dry out after months of applying and removing them from different plants. Similarly, maybe you've lost your leads or want to have an extra pair so you can easily compare the signal from different plants without having to remove and reattach pads from the leaves.
Lucky for you, these parts are relatively easy to come across and fairly inexpensive. With that, here are some recommended replacements.