Birdsboro Which year is this?
Hard to say based on interwebs search. The current line is PRIME 13, so it's 7 iterations old, but I don't know if that means annually. The specs seem the same. 460cc, 35-36g shaft with 6+ torque, total weight 257. Looks like the "regular" line of clubs are at V14, the Prime line being the ultra ultra light.
Additionally, I bought this driver from Japan, so maybe PRIME 6 predates Dunlop shipping to USA.