Look at the comments/Q&A -- they're allowing people to overpledge and then in your "shipping info" ask for the other rear light. Not sure they'll allow an infinite number of different overpledge options, but this was a request of a lot of people. (I mostly want 1 front and 2 rear -- the bike I'm planning to put them on is a city commuter, and these will be additional visibility/running lights to the battery ones it already has.)