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&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;The Company
purchases a number of components from various sources. In some
cases, alternative sources of supply are not available. In other
cases, the Company may establish a working relationship with a
single source, even when multiple suppliers are available, if the
Company believes it is advantageous to do so due to performance,
quality, support, delivery, capacity or price considerations. If
the supply of a critical material or component were delayed or
curtailed, the Company&amp;#x2019;s ability to ship the related product
in desired quantities and in a timely manner could be adversely
affected. Even where alternative sources of supply are available,
qualification of the alternative suppliers and establishment of
reliable supplies could result in delays and a possible loss of
sales, which could adversely affect operating results.&lt;/font&gt;&lt;/p&gt;
&lt;p style="MARGIN-TOP: 6px; MARGIN-BOTTOM: 0px; MARGIN-LEFT: 4%"&gt;
&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;As of
December&amp;#xA0;31, 2009, approximately 65% of the Company&amp;#x2019;s
total employees, including those of the subsidiaries, were union
members, and production employees accounted for substantially all
of these members. The Company has a collective bargaining
arrangement with its labor union, which is negotiated once a year.
If the Company&amp;#x2019;s relationship with its employees deteriorates
and there is labor unrest resulting in a work stoppage or strike,
the Company&amp;#x2019;s production facilities will not be able to
continue operations and this will have a material adverse effect on
the Company&amp;#x2019;s financial condition and results of
operations.&lt;/font&gt;&lt;/p&gt;
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      <ElementDefenition>Description of any concentrations existing at the date of the financial statements that make an entity vulnerable to a reasonably possible, near-term, severe impact. The entity should inform financial statement users about the general nature of the risk associated with the concentration, and may indicate the percentage of concentration risk as of the balance sheet date. Disclosure of any financial instrument credit risk concentration also should indicate the maximum amount of loss that would be incurred upon complete failure of the counterparty to perform and the entity's collateral policies or other policies that limit the loss exposure. This element may be used as a single block of text to encapsulate the entire disclosure including data and tables.</ElementDefenition>
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 -Name Statement of Financial Accounting Standard (FAS)
 -Number 107
 -Paragraph 15A

Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher AICPA
 -Name Statement of Position (SOP)
 -Number 94-6
 -Paragraph 21, 22, 24

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