7 Oil and gas well machine parts, namely, sand control screens for use with well drilling machines in the oil, gas and energy industries; Oil and gas well machine parts, namely, high performance sand control screens for use with slotted liners for use with well drilling machines in the oil, gas and energy industries; Oil and gas well machine parts, namely, self-cleaning, plugging resistant sand control screens for use with well drilling machines in the oil, gas and energy industries; Oil and gas well machine parts, namely, sand control devices in the nature of self-cleaning, plugging resistant sand control screens for use with well drilling machines in the oil, gas and energy industries