Thomastik P18 Brass Plated Plain Steel Single String .018 Gauge Brass Plated Plain Steel String. The same plain steel strings that are used in Thomastik’s Spectrum Bronze, Plectrum Bronze, George Benson, Jazz Swing, Jazz BeBop, Power Bright and Blues Slider Sets. Made in Austria to seriously high spec! Ideal for creating your very own custom gauge set of strings, replacing a broken string or keeping as spares in your gig bag or case.