The wooden top board, which fits onto the mortar stand, is absorption sealed, meaning it prevents plaster/mortar being absorbed by the wood.
As the top board does not absorb moisture, plaster/mortar and any remaining dry mix can easily be cleaned off.
Underneath various top boards there will be non-slip location points to match the mortar stand and create a stable work surface. Each tube of the stand is fitted into the corners of these location points.