Best single injector I've used is Do-It's 9 oz injector. Yes shocking I'm endorsing something Do-it as just about everything else I've used from them has been junk in one way or another. It locks and gives me the capacity to shoot multiple molds at once. Also the plunger doesn't extend past the injector shaft unlike Basstackles. I had to clean my Basstackle injector consatantly due to the plunger allowing plastic to get trapped inside the chamber. My Do-It I've cleaned zero times and going on 3 years now. For dual injector now hands down Basstackle.