Avent Natural bottles?

ljlkm

A few weeks ago, someone was recommending the Avent Natural bottles, but I'm not sure exactly what they are.  I went to Target and BRU today to look for them, but they didn't have them.  And looking online, they look like the regular Avent bottles.  Can someone link what they are?  DS loves the Avent nipples but the leaking bottles are driving me crazy!