A system, method and computer program product are provided for programmable vertex processing. Each of the two split outer ring halves includes an oil hole penetrating the split outer ring half in a radial direction thereof and an oil groove formed on an outer diameter surface of the split outer ring half along a circumferential direction thereof to allow the oiling passage and the oil holes to communicate with each other. Channels along the top and bottom edges accept two panels to form a studless wall having an inner and outer panel.