The realistic looking black colored ceramic frag plugs are unlike aragonite frag plugs, and do not need to be cured. They are fired at over 2000 degrees for several hours. This prevents any ph spikes that are common from aragonite frags that usually are never fully cured leading to a major die off in your tank. All of our frag plugs have easy break away stems for those who wish to have a disk or no holes in there live rock. We also make our crowns as thin as possible to allow for growth to cover over the edges sooner then some thicker crown plugs on the market. These frag plugs are great for mounting LPS, SPS, Birdsnest, Montipora, Xenia, Acropora. They have shown to promote coralline algae growth and corals. They are black colored crowns with 3/4" crowns and a stem diameter that's 3/8" to 1/2" to allow for varying sized holes and needs. They sit approximately 3/4" tall. We have designed our plugs to have a more natural look once placed in a rock or crevice with curves to flow with the natural rock work.