This terra cotta Olla Spike comes with a glazed cap. The spike is designed to easily push down into your raised bed planter or pot (as long as the soil is loose it should easily push right into it) or you can dig and install that way. A great water conservation tool! Many people have reported not using the lid, but instead installing a wine bottle or liter bottle inverted into the top so that they can water for an even longer time frame if they are going out of town. As with most olla's they keep the soil moist up to about 1 ft or more in circumference. They hold approximately 2 1/2 cups of water and are approximately 2.5"W x 11"H.