Our glass deco/suncatcher colour pens can be used on glass, window, ceramic, tiles and other smooth surfaces. If you need outlines, use glass deco outliner pens. You may draw on our yellow release cards or draw straight on intended surfaces. Our colour is certified: Non-Toxic Water-Based Safe For Children Conforms to International Safety Standard EN71 and ASTM D4236 Content: 10 x 11ml Glass deco/suncatcher colour pen