I bought this battery to replace the original 3 year old battery in my Bold 9900. The old battery had started to fail, discharging suddenly, recharging unusually quickly and otherwise behaving strangely. This replacement has since (two weeks later) resumed normal service. The rate of discharge is predicable, faster during heavy use, slower when on standby. The price is significantly less than you would expect to pay and seems so far to return good value for money.