4 strips of Copper Strip, Shimming, I have a roll, 3.5cm wide. i cut off 4 no pieces 20cm, so they fit inside envelope and normal letter postage, thickness is 7.5/1000 ( thousandths of inch) or 0.2mm slightly thicker than Chinese takeaway container. there is water staining on all of what I have, easily brightens with wire wool, if required. ideal for engineering etc. Post uk only.
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