I think it is P0, if I remember correctly. I charge my transmitter batteries at 1A.
edit - I used P0 with the original Panasonic and Sanyo 3000's, and would have used it with the Stock and Ultra Metals also. With the Sanyo 3000HV's, and the GP's I would use CS, because they like a higher peak detect. I think CS uses a .05 threshhold, perfect for GPs, and it gives you a 10 minute long-lockout so they don't false peak.