IINM Canada is a metric country (though I believe that Imperial measurements are also used). Here in China, there is a thin wall PVC sewer pipe that is metric, and its ID is over 4". Does the same hold true for Canada. I'm hoping that I might be able to source some in Canada to send to eRockets to protect my Binder Design Raptor in its journey here (it would save me sending some from here, and likely be cheaper). Thanks!