The professional and production adapters from Batronix and Winslow Adaptics allows easy and fast working. You can put the chip into the adapter and close the "clamshell" which take for a safely connection. After the programming procedure is finished, you push at the button on the top of the "clamshell" and it will jump up. The "low-cost" Adapter are a cheap solution for programming plcc chips. You will have to press the chip into the adapter. After the programming procedure is finished, you can pull the chip out of the adapter using a PLCC extractor tool.You can find additional information about each adapter in its datasheet.