Score High Modeling Clay is used to prevent epoxy from going where you don't want it to go. This non drying soft, tan, modeling clay is excellent for filling pin holes and recesses in whatever metal parts you are trying to epoxy bed. Failure to prevent epoxy from going into recesses and pin holes will result in damage to the stock be bedded when the metal is removed. NOTE: modeling clay can easily be reclaimed and used time and time again.