Contains 55 6" pieces of single wall 2-1 polyolefin, I.D. ranges 1/8" - 1/2" in red, black, yellow and blue. Shrink tube is UL listed E-35586 and MIL-1-23053/5. Excellent for securing and insulating almost any wire connection. All contained within a durable, lightweight, translucent carrying case (7" x 3" x 1-1/2").