Easy-to-read dial gauge for accurate pressure control. Air vent/cover lock allows pressure to build only when cover is closed properly, prevents cover from opening until pressure is safely reduced and gives visual indication of inside pressure. Extra strong, warp-resistant aluminum construction for fast, even heating. Includes cooking/canning rack and instruction/recipe book. UL Listed. Replacement parts including Orgill Nos.680.3316 Sealing Ring, 699.2028 Over Pressure Plug, 625.5236 Pressure Regulator,and 615.9735 Cover Handle sold separately. No.01751 will hold 7 Qt , 10 Pt or 24 1/2-pint mason jars. No.01781 will hold 7 Qt , 20 Pt or 24 1/2-pint mason jars.