Monster Standard UL CL3 Speaker Cable 16 Gauge - 500 ft. spool (S16-2R CL-500) Two conductor CL3 and FT4 rated speaker cable for in-wall installation. EZ-Strip ripcord for quick, easy jacket removal. Monster quality in a low-cost design. 14 and 16 gauge constructions with fine, high purity copper stranding. S14-2R CL: THX maximum lengths: fronts 30 ft; surrounds 60 ft.