Chip for the Ultimate3/3S QRSS kit, v3.09f. This is the ATmega328 chip.
Note that this is the chip for the Ultimate3/3S Kit, it will work in both the U3 and U3S kits. But it is not for the older retired Ultimate (U1) kit or Ultimate2 (U2) kits! This chip is not compatible with the old kits!
Version history: please see http://www.qrp-labs.com/ultimate3/u3firmware.html