<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>124 - Disclosure - Financial Instruments</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

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&lt;table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%"&gt;
&lt;tr&gt;
&lt;td valign="top" width="4%" align="left"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;&lt;b&gt;15.&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" align="left"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;&lt;b&gt;Financial
instruments:&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
&lt;p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 6px"&gt;
&amp;#xA0;&lt;/p&gt;
&lt;table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%"&gt;
&lt;tr&gt;
&lt;td valign="top" width="4%" align="left"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;(a)&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" align="left"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;Concentrations:&lt;/font&gt;&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&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;During the
years ended March&amp;#xA0;30, 2013,&amp;#xA0;March&amp;#xA0;31, 2012 and
March&amp;#xA0;26, 2011, approximately 28%, 26% and 24%, respectively,
of consolidated sales were of merchandise purchased from the
Company&amp;#x2019;s largest supplier.&lt;/font&gt;&lt;/p&gt;
&lt;p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 6px"&gt;
&amp;#xA0;&lt;/p&gt;
&lt;table style="BORDER-COLLAPSE: collapse" border="0" cellspacing="0" cellpadding="0" width="100%"&gt;
&lt;tr&gt;
&lt;td valign="top" width="4%" align="left"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;(b)&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top" align="left"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;Fair value of financial
instruments:&lt;/font&gt;&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&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;Fair value is
defined as the exchange price that would be received for an asset
or paid to transfer a liability (an exit price) in the principal or
most advantageous market for the asset or liability in an orderly
transaction between market participants on the measurement date.
U.S. GAAP establishes a fair value hierarchy which requires an
entity to maximize the use of observable inputs and minimize the
use of unobservable inputs when measuring fair value. U.S. GAAP
prescribes three levels of inputs that may be used to measure fair
value:&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;Level 1 &amp;#x2013;
Quoted prices in active markets for identical assets or
liabilities. Level 1 inputs are considered to carry the most weight
within the fair value hierarchy due to the low levels of judgment
required in determining fair values.&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;Level 2 &amp;#x2013;
Observable market-based inputs or unobservable inputs that are
corroborated by market data.&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;Level 3-
Unobservable inputs reflecting the reporting entity&amp;#x2019;s own
assumptions. Level 3 inputs are considered to carry the least
weight within the fair value hierarchy due to substantial levels of
judgment required in determining fair values.&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;The Company has
determined that the carrying value of its cash and cash
equivalents, accounts receivable and accounts payable and accrued
liabilities approximates fair values as at the balance sheet date
because of the short-term maturity of those instruments. For the
$67.3 million of bank indebtedness and $8.2 million of long-term
debt bearing interest at variable rates, the fair value is
considered to approximate the carrying value.&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;The fair value
of the remaining $33.7 million of fixed-rate long-term debt, which
includes $18 million of debt that becomes floating rate debt if
interest rates rise above a certain level, is estimated to be
approximately $36.3 million. The fair value was determined by
discounting the future cash flows of each instrument at the current
market interest rates for the same or similar debt instruments with
the same remaining maturities adjusted for all necessary risks,
including its own credit risk. In determining an appropriate spread
to reflect its credit standing, the Company considered interest
rates currently offered to the Company for similar debt instruments
of comparable maturities by the Company&amp;#x2019;s lenders. As a
result, the Company has determined that the inputs used to value
these long-term debts fall within Level 3 of the fair value
hierarchy.&lt;/font&gt;&lt;/p&gt;


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