While it stung a little, I expected that with 20% L-Asorbic Acid but the...

While it stung a little, I expected that with 20% L-Asorbic Acid but the results were fantastic. I received this as part of the best of dermstore kit and really liked the serum, but the bottle and pump are problematic. It took at least a couple min every day to get the pump to work initially and then it just stopped working entirely.