Oxypex tubing can also be used in snow melting applications. This tubing complies with DIN 4726 as endorsed by the Hydronics Institute. Oxypex is made to copper tube size outside dimensions and a standard dimension ratio of 9 and is available in the following nominal sizes: 3/8", 1/2", 5/8" 3/4" and 1". It is available in coils up to 1200' long which are �fooarked�.