Frequently Asked Questions Are Philips Avent cups compatible with other Avent products? Philips Avent Sip No Drip cups are designed to fit the entire Avent range. Find out which products fit your cups. Compatibility Philips Avent Sip No Drip cups The cup is compatible with the Natural bottle, screw ring and nipple. The Natural nipple can be bought separately; the Natural screw ring comes with the Natural bottles. The spout together with the ring with handles of the cup is compatible with the cups/bottles of Classic (including adapter ring), Natural and easy sip. The cup is compatible with Philips Avent Storage cups and manual breast pump. What is not compatible? The Classic nipple and easy sip spout cannot be used with the ring with handles of the Sip No Drip cup.