Heidi Swapp Lightbox Alphabet & Numbers Mega Pack Inserts. Create even more clever phrases and fun decor for your Lightbox collection with the black mega pack. The mega packs include not only the alphabet but numbers and punctuation too! Color: Black. Includes: 100 pieces. WARNING: This product contains chemicals known to the State of California to cause cancer, birth defects or other reproductive harm. Do not mouth or chew.