the output had the polarity inviertes and I had to curs both of the cables and reattach them.
The actual capacity is about 2000 mAh at 1 A discharge (C/3)! Conditions for the test are: charged with a 12.6V, then 3 days later (initial voltage showed 12.31V) discharged at 1000 mA. Also, self-discharge is quite high: went from 12.47V to 12.31V over 91 hours, which means about a 7% loss of energy in 3 days. Safety electronics seem to work: it cut-off when charged enough and also when discharged to prevent over-discharge.