Plastic yes, urea plastic...I'm not so sure. It doesn't have the same *clink* sound when dropped on a hard surface as other urea nuts I've had. Fits CE teles and starts with not a lot of sanding to fit, though mine had injection molding edges on the bottoms that would have needed to be cleaned up regardless. Fine to throw on a cheap guitar, but don't think that this would be an upgrade from your stock nut unless it's ABS. Probably better to spring for TUSQ in most cases, if you want a decent drop-in solution.