The Difference Between Runner and Block Wooden Pallets
Runner Wooden Pallets:
Runner pallets use a frame of three or more parallel pieces of timber (called runners). Typically, runner pallets are held together by three wooden runners, one running along each side of the pallet and one through the middle. The top deck boards are then affixed to the runners to create the pallet structure. Runner pallets can have a notch cut into them allowing "four-way" entry. Forklifts can lift a runner pallet from all four directions, though lifting by the stringers is more secure.
Block Wooden Pallets:
Block pallets are typically stronger than stringer pallets. Block pallets utilize both parallel and perpendicular stringers to better facilitate efficient handling. The block pallets are held together by square or rectangular wood blocks, sometimes with additional boards around the perimeter that reinforce the top and bottom decks. A block pallet is also known as a "four-way" pallet, since a pallet-jack may be used from any side to move it.