A stringerboard is a board running lengthwise between the deckboards and support blocks in a typical block-style pallet. It provides a connection surface within the deck assembly. Although its name resembles stringer, it is a distinct part: the blocks establish the separation between the decks, rather than a full-depth stringer doing that job.
The distinction matters when reviewing a drawing or identifying a damaged component. Calling both parts a runner can leave a supplier unsure which piece you mean. Mark the location on a photograph and use the drawing’s component names when discussing dimensions or a replacement specification. For the larger design context, refer to AR Pallets’ guide to pallet construction methods.