Let me explain. C1 is capacity x 1. So your 600 mah pack, C1 would be 600mah or .6 amp.

C/10 is Capacity / 10. So your 600 mah pack, C/10 would 60 mah or .06 Amp.

A C/10 charge takes about 15 +/- hours to reach full charge. A C1 charge would take about 1 +/- hour to fully charge.