How to include my class in my block blocktheme-xxx.tpl.php?

Hi!
Please, tell me.
My class: wood
How to include my class in my block blocktheme-wood.tpl.php?

this is code my block block.tpl.php

            <div class="rt-block">
	<?php if (function_exists(block_class)) ?>
	<?php if ($block->subject) : ?>
		<div class="module-title">
			<div class="module-title2"><h2 class="title"><?php print $block->subject; ?></h2></div>
			<div class="clear"></div>
		</div>
	<?php endif; ?>
			
				
	<div class="module-content">
		
		<?php print $block->content; ?>					
	</div>
			
	</div>