You are viewing AVENT Dome Caps by Phillips.  These durable dust cover caps are made from BPA Free Plastic, ensuring a quality fit to protect the sippy spout from contamination to keep your child safe! We are selling these items as 2 packs at 4 caps per pack. So if Quantity 1 is selected above, you will receive a total of 8 caps.  If Quantity 2 is selected, you will received 16 caps in total.  These caps are the standard Avent size, and they fit the Klean Kanteen Sippy Kanteens perfectly, as well as many others.  Please inquire with any questions before purchasing.  Thanks for your interest!