Is this ok for cascade?

[JSU]

http://www.uniweld.com/catalog/refrig_hvac/hoses/silver_magic_hose.htm

also the parker 510A-6 its only rated for -40c but will it work?

[chilly1]

Yes these I have used for both 1/2 inch and 1/2 inch lines at -100C the work fine I would refrain from moving them at these temperatures.

[JSU]

"both 1/2 inch and 1/2 inch lines" you mean 3/8? Thanks for the input!