My favorite feature is the click. Cheesy as it sounds, there have been countless times when I thought I had a top on, only to have it leak all over the place. This cup clicks right into place so you know it is on correctly and won't leak. It also had a cute pattern on it that was fairly gender neutral...I hate that many cups are either pink/purple or blue/green!
These cups are available online at Amazon, Wal-Mart, and Target.
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