Mulberry Studios Top Dad Racing Pen - Pro Grand Prix Pen - Brand New Factory Sealed Shop Stock Room Find. Released by Mulberry Studios as part of there Pro Grand Prix Pen Series. This fantastic Racing Pen is a push button retractable pen that features Top Dad on the side, has rotating wheels and is great run to write and race with. Brand New And Factory Sealed Shop Stock Room Find. Discovered in the store room of a closing down shop. All Orders Received Before 4.00pm Mondays to Fridays are shipped the same day