formvar

A spool of slightly less than 100 feet of number 17 Heavy Formvar wire was required for the secondary winding.

一卷大约100英尺的17号线足够完次级绕组。

It required three spools, each containing approximately 900 feet of number 27 Heavy Formvar wire for the primary sections.

这个工作需要三个线轴，每个上面有900英尺27号线来绕制初级绕组。