There are two basic Mod-Pots product lines; the 70-series and the 388/389 Series.

The 388 and 389 series products have roughly 25 “standard” configurations, yet can be supplied in millions of variations.  There is simply no way to accommodate every variation so instead, a unique number is assign to each design.  In addition to the specifications, each unique design is associated with the original customer and would include any special marking or testing requirements.

The 70 series has a part numbering scheme which is limited to single shaft,  single or dual potentiometers with all sections having the same resistance values.  The part number breakdown for most products that fit that description is contained in the 70-sereis literature.  However, there are literally millions of designs that cannot utilize the standard 70-series part numbering scheme and for those items, a unique number is assign to each design. In addition to the specifications, each unique design is associated with the original customer and would include any special marking or testing requirements.