1968 Mattel Plastix pack of BLACK refill units for the Injector play set.  The Injector set was a set similar to the Thingmaker, but you molded little plastic cowboy/western figures.  This listing is for an unused package of the BLACK plastic “pills” used as the raw material in the molds.  The package has some wear but the contents are still firmly attached to the backer card.  See pics for details.  Buyer pays shipping.  Payment due within 2 days of auction end. All items ship within 3 business days.  Thanks for looking!