Type AN - without lock nut, with stainless steel knob
Type AKN - with lock nut, with stainless steel knob
GN617.1 Indexing Plunger, with Rest Position, Stainless Steel
These are used for such applications where the plunger has to stay in its retracted position. To achieve this, the knob is rotated by 90° degrees after being retracted. A notch keeps the plunger in this position.
Stainless Steel NI AISI 303 - plunger chemically nickel plated
Knob - Stainless Steel NI AISI 303, not removable