Note 4 - Inventory (Detail) (USD $)	Jan. 31, 2013	Apr. 30, 2012
Inventory Valuation Reserves	$ 668,000	$ 677,000

The amount of the valuation account as of the balance sheet date which reduces the carrying amount of inventory to net realizable value; takes into consideration such factors as market value, excessive quantities based on expected sales, technological obsolescence, and shrinkage. May also provide for estimated product returns or price concessions pertaining to product cost.

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+ Details