avent bottles????

ok..i was on there web site and didnt find my answer htere, so i always seem to get it here from every one so....
does the regular advent bottle ((rings and nipples)) fit the advent bottles with the drop in bags....or is it two completly different sets you need to purchase...i already have the regular advent bottles, but was thinking the drops bags would be easier to travel with...(((no washing bottles just throw out the bag and wash the nipples))...any help would be greate..thanks ladies...