Sealing: The grading marks are clear and well printed, and the black measurement marks on the side are easier to read. The plunger works smoothly and the rubber tip on the plunger makes a good seal. -Safety: Each syringe is individually sterile packaged, clean and sterile. Material: Each syringe is made of 100% medical grade plastic Product includes: 20ml 30packs Package size:20ml 36cmx26cmx4cm.