Zareba Systems Large Fence Tension Springs (10 Pack)<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>10 units per order</li><li>Measures wire tension on the fence line</li><li>One inch of compression equals 150 lbs. of tension</li><li>Helps absorb expansion and contraction of the fence wire</li><li>Use one with every in-line strainer</li></ul></div><img src="http://ecx.images-amazon.com/images/I/41XRJhKGumL.jpg" noproxy>