Those look like the type of molex connectors in a computer, only with two slots...
If it helps, the Digikey part number for a 4-slot molex connect is A1403-ND (catalogue page 106 -
http://rocky.digikey.com/scripts/Pro...7&M=1-480305-0 ) - I'm sure of this because I've bought this exact item from Digikey before.
I tried looking around for a 2-slot version, but the descriptions were too cryptic for me (i.e. Panel-Mount Rectangular Connectors vs Free-Hanging Rectangular Connectors). Perhaps someone can use this information to find the Digikey part number for this item?
(NOTE: If you buy from digikey, you also need to buy the individual pins seperately. Digikey also tacks on an extra $5 handling fee if your order comes out to less than $25, so you might as well purchase all your robotics electrical needs now)
[Edit]
Assuming what you're looking for can be described as a 'Free-Hanging Rectangular Connector', I believe the Digikey part number is A1411-ND for socket housing (female?) and A1410-ND for pin housing (male?). Someone who knows exactly what this part is should double check me, though...