Four 1-inch TargetTacks are required to properly secure and hold in place, commonly used paper-based targets, for supported substrates. If you are using larger sized targets, over 16 inches tall and wide, you may require additional TargetTacks to securely hold and/or minimize wind movement of larger sized paper-based targets based on substrate, substrate covering, or exterior used. Please read and save instructions with included warnings, before each use to ensure instructio