The tube portions are fabricated from 304 stainless steel. For increased resistance to corrosion in downstream semiconductor processes, some ISO flanges and fittings are available in 316L stainless steel. Ebara makes its own elbows, and all tees and crosses are made with the pulled-port technique. This allows smooth, crevice-free butt welds to provide the maximum in cleanliness for UHV applications. Fittings are shown with OF flanges only. To order a fitting with nonrotatable flanges substitute ?-N? for ?-OF ? in the model number. Fittings are also available with CF (Conflat style), KF (ISO-KF compatible) and ASA flanges. Standard finish is bead blasted. Electropolished finish also available.