the motors are hacker Style Brushless Outrunner 20-50S
i use 8045 props.
and use a multiwii lite CRIUS MultiWii Lite Edition Flight Controller v1.0 for mini Quadcopter $16.72 Free Shipping @GoodLuckBuy.com

i think the arms are 6mm but i cant remember how heavy they were, i think its close to 500g flying weight. To be fair i could save alot of weight on the arms and the center plate but wasnt sure on the stiffness of the design and may swap the ali center plate for a glassfiber one. it flys pretty well and hovers at less than half throttle which is pleasing. just need to learn to fly the thing better now haha.

I also have a hexacopter which is one of these Flyduspider Hexacopter Frame Set which is really nice but a bit scary to fly and expensive in props if it all goes wrong.

something id suggest is not to use connectors between your motors and esc's as ive had one work loose before which isn't good mid flight. I think other people have had this issue before also.