From the photos it looks like it has no cutting edge and I agree with that. But this caulking gun doesn't have a sealbreak either (which is what I thought after reading the questions). I could have bought a cheaper gun that had all the features. As for the seal, it's no different than the cheap caulking gun I used to have. The flow is not smooth and the thumb button does NOT stop the flow. This cartridge gun is not worth the price.
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