Here is some of the better insulators. CD 162 McLaughlins in cornflower blue, dark delft blue and clear; CD 252 Knowles No. 2 Cable in blue; about a dozen CD 297 Fred Lockes No. 16 in dark aqua; CD 162 N.E.G.M.co. in ice blue; CD 292 Patent -Other in aqua; CD 20 E.S.B.Co. in light aqua; and a couple of impurity pieces: CD 162.1 Star with a big loopy amber streak and a CD 133 CREB with a couple of olive squigglies. Look for them on eBay in the near future. Here is the one I saved for myself [id=216392048]