Oil-Filled Slippery UHMW Polyethylene Rods This oil-filled material is self-lubricating for an extra-slippery surface. Metal-Detector-Grade Slippery UHMW Polyethylene Rods If a chip of this material breaks off, it can be located by metal detectors to reduce ntamination risks. Metal-Detector-Grade Slippery UHMW Polyethylene Sheets