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The Filmsticks T-Marker Kit lets you lay down marks on stone or wood, as well as places that chalk or tape just won't do well such as dirt, grass, and wet surfaces. The kit features seven different colored rubber T-markers, one each in green, blue, red, pink, yellow, white, and black. The markers are reusable and washable, so you can use them over and over again, whether inside or out.
Merely drop the T-Marker down on the floor or ground so your talent knows where to start or stop. The different colors allow you to reserve one color for each different actor, helping to prevent confusion about whose mark belongs to whom. A built-in hole allows you to carry these on a carabiner for easy carry and access.