1987–2001: New Process NP231 Command-Trac, part-time only, 2.72:1 ratio with low range
NP231 has the following settings: 2HI, 4HI, N, 4LO
1987–2001: New Process NP242 Selec-Trac, full-time/part-time, 2.72:1 ratio with low range
NP242 has the following settings: 2HI, 4 full-time, 4 part-time, N, 4LO