SuperKlean's brass and stainless steel hose racks, made out of321 series stainless steel, are virtually corrosion resistant in most applications and environments. Its aluminum epoxy coated mounting plate was specifically designed for quick and easy installation and meets the required spacing between wall to plate and plate to units. Model #Description: 12-SS300 series stainless steel hose rack for wall mounting (includes stainless steel mounting plate, stainless steel bolts, stainless steel end fittings, an 4stainless steel anchor bolts) 12-S300 series stainless steel hose rack for wall mounting (includes stainless steel bolts, epoxy coated aluminum plate and stainless steel end fittings) 12300 series stainless steel hose rack for wall mounting (includes stainless steel bolts, epoxy coated aluminum plate and brass end fittings) 11-S300 series stainless steel hose rack for unit mounting (includes stainless steel bolts & stainless steel end fittings) 11300 series stainless steel hose rack for unit mounting (includes stainless steel bolts & brass end fittings)