Easy to use and to disassemble: Adjustment openings for computer bags, shoulder bags, travel bags, briefcases,suitcases etc. 4 pieces Fake Blood Needle Syringe Pens. each pen measures 5 inches, filled with fake liquid medicine syringe. Safe and easy to use with a single push of the top, tip of the pen will show up and you can write memos, letter, list or notes for more fun and laughter, small button to retract and hide the tip. Amazing party favors, helps to add more fun and excitement at party, children will love these and also adults. You can also use it for many situations such as school, , anniversary celebration, public relations planning, business gifts.