This replacement head works just fine, but not as well as the original lid it replaced. I make a smoothie every morning for breakfast with frozen avocado, frozen spinach, protein powder, and almond butter. The original blade lid got through everything without a problem, whereas with this lid I still find some small bits of spinach or avocado every now and then. It also gets a weird film on the plastic part that I tried to wash off normally, but would only come off with a scrubby pad (same smoothie recipe for both heads, but the original head would wash just fine).Otherwise it's fine. It fits properly and seals completely, and it works just fine as a non-brand replacement head. I don't know if I'll buy it again as my next replacement head (hoping to find one that has sharper blades that will actually cut through the veggies fully) but for the price it was a good buy.