yourATCstore Halloween ATC Collage Sheet. This Halloween sheet was designed for making ATCs with. There are 14 Halloween Inchies, as well as other vintage cards, photos and sayings. Perfect for other Halloween altered art projects too. These matte finish collage sheets are professionally printed on professional presentation paper and come in a crystal clear bag for protection. Each collage sheet measures 8 1/2" X 11" and is acid free.