Yep, the 1" brad point is for the 4A plugs. I find the brad point works better than an auger or bulb planter bit. The auger bit just fills with dirt where the brad point self cleans much better. Once in a while dirt will stick to it but, just running your glove down the bit is fast and easy. The auger bit not so much. I have not planted other sized plugs but you would just size accordingly.