Unique end plate design allows 5° or 20° slant when rack is set down on side. Autoclave media upright, then allow to cool on a side. Media will harden with perfect, consistent slant. Also useful for incubating liquids on a slant for better aeration. Rack holds 40 tubes (4 × 10 array); keyed with numbers and letters. Stackable; will not float in water bath. Autoclaving will reduce strength over time.