Fitted a very heavy nylon line to my 36 volt cordless line trimmer to see if it could handle it. Works fine, I've had the trimmer for a year but only used it once because the line supplied with it is near on useless, I reckon it should have something in between the two extremes tried thus far. I reckon I'll go with the next-smallest diameter line to wot it currently has. I'm being really generous and charging it up for the 4th time ever.