This later example of the Alcotest CH 237 has five tubes and five mouth pieces located internally on both the top and bottom of the plastic green case. This new layout also incorporated a cradle (with clip) on each side, one for the blowing bag and the other for the instruction booklet. The original layout had all 10 tubes and mouth pieces located on the bottom section of the green case without any holders for the blowing bag or instruction booklet.