<html>
<head>
<style><!--
.hmmessage P
{
margin:0px;
padding:0px
}
body.hmmessage
{
font-size: 12pt;
font-family:Calibri
}
--></style></head>
<body class='hmmessage'><div dir='ltr'>Is there any rule of thumb for how much difference between individual cell resistances is OK before a back should be retired?<div><br></div><div>Regards,</div><div>Mike C</div>                                     </div></body>
</html>