40-100 Nickel Medium Light Electric Bass String pack from Warwick. This Warwick Nickel Medium Electric Bass String Pack 40-100 is for 4-string basses. The set consists of .040″ .060″ .080″ .100″ sizes. The strings are made of Nickel Plated Steel. These Warwick bass strings boast carefully chosen materials. The adjustment of core and winding wire give an even tension well balanced overtone responses as well as an even magnetic response when being picked up.