You will get Schlumbergera hybrid zygocactus, Christmas Cactus Plant - 3.5 inch pot.
This plant comes in a 3.5" pot. You will receive a very similar plant to the one in the picture. It may or may not be blooming at the time of your purchase. The plant is shipped in its pot to prevent any damage to the roots.
This is actually a hybrid of Schlumbergera, a small genus of cacti with six species found in the coastal mountains of south-eastern Brazil. Plants grow on trees or rocks in habitats that are generally shady with high humidity, and can be quite different in appearance from their desert-dwelling cousins.
This epiphytic cactus needs very porous soil, filtered light and water thoroughly when soil is dry. Hardy to 40 °F.