Editor Reviews:

Product Description:
SipEase valves make Playtex Spill-Proof Cups spill-proof. They're designed to dispense liquid only when your child is sipping. Replace worn or lost valves with this refill pack. Features One-piece valve is activated when child sips Easy-to-clean Fits all Playtex Spill-Proof Cups 2 per Package

Rating : - Must have!
Good luck finding these kid must haves in stores! I used to pick these up when need at Target and at Wal-mart, bu tin the last 6 months these have vanished from both places! I haven't checked grocery stores and pharmacies, yet...but I'll bet the internet is much easier than hauling kids in and out of candy and commercial treasure filled stores any day!