DR Strings MLR-45 Hi-Beams 45-100 Electric Bass Strings String gauges: 45 65 80 100. Hi-Beam stainless steel bass strings are round wound and constructed on a round core which is unique in the industry. Hi-Beams require much more time, care and extra steps to make than other bass strings. The extra effort DR expends making Hi-Beams results in a bass string that is highly flexible and musically but not harshly bright. They are renowned for durability, unusually long life, consistency and string-to-string balance. They don’t eat your frets. HI-BEAMS are the string to choose for brightness, punch and ease of playing.