Silver SK-325 appeared on the market in the mid-1970s. It is a standard-gauge knitting machine, with 200 needles, 4.5 mm apart. Silver SK325 accepts punchcards to create patterns by mechanically selecting needles according to the holes in these punchcards. It is potentially the first model to have a built-in knit leader.

Except for the color, Silver SK325 is identical to Studio mod. 326. One exception is:

Silver SK325 is probably the last model with just one lever on the pattern panel: to release the punchcard so it advances when the machine knits patterns. All later models (starting with Silver SK326) have a second lever to expand the pattern vertically by a factor of two. 

Thus, read the corresponding article with all its pros and cons. It is also very similar to other punchcard-capable knitting machines with built-in knit leader, such as SK322, SK325, SK326, SK328, and SK330, to name a few.