M Series Rotary Switch. The M series half- inch rotary switches are designed for use in a wide variety of applications including test equipment, industrial equipment and medical equipment. For durability they have a stainless steel actuator and non-shorting contacts. Metal bodied rotary switches with 36° indexing for panel mounting Break before make contacts Panel cut-out: Ø6.35mm Shaft: Ø3.17mm; Length: 10.15mm