Two Little Fishies O-Ring for 550 Model Reactor<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Description: replacement O-ring for the PhosBan Reactor 150</li><li>Two Little Fishies O-Ring for 550 Model Reactor</li><li>To be used with a Reactor 550 only</li></ul></div><img src="http://ecx.images-amazon.com/images/I/31zCmPYJ28L.jpg" noproxy>