FIBRE CRAFT-Creative Hands smART Parts Rocket Writers. These rocket writers have an adjustable nozzle allowing you to write with a fine line or bold! This package contains four 1.01oz/30ml writers in red; green; blue and violet. Contents conform to ASTM D4236. Recommended for children ages 3 and up. WARNING: Choking Hazard-small parts. Not for children under 3 years. Imported.