A system employing vector signal generator and vector signal analyzer modules or cards that are configured to test multiple devices under test simultaneously. A plurality of prisms extending in one direction are provided on one principal surface of the optical member in regions on both sides when divided at a virtual plane that includes a reference axis. The masking devices are die-cut into various shapes and sizes, and placed on rolls of release liner so that they may be readily applied to parts requiring masking during a painting or coating process. The packaging apparatus may have a structure for mating and locking the outer packaging member to the inner packaging member for facilitating engagement and disengagement.