Design: Supplied with adjustment rings and screwdriver, in a plastic case. Set contents: 1 x 2-point internal gauge 3–4 mm 1 x 2-point internal gauge 4-5 mm 1 x 2-point internal gauge 5–6 mm 1 x adjusting ring Ø 4 mm 1 x adjusting ring Ø 5 mm 1 x adjusting ring Ø 6 mm 1 x extension