60 cm (2 feet) 5 mm heat shrink tubing, red and black

This heat-shrink tubing is to insulate and protect connections and wires in electronic circuits.

5mm is the original size. It shrinks with a heat gun or lighter, to 2.5mm, which is suitable for 3.5mm bullet connectors and wires.

Recommended size is 1/2 inch (1.5cm). So this package will make 15 red and 15 black sleeves.