Beisler 1220-4 - Manual (Page 49)

Chapter 6: Operation
Page 6-25
Pict. 23 Rear needle protection (2)
Pict. 24 Rear needle protection (3)
When the top of the left grab stands in the middle of the needle, the
needle protection ((2) in Pict. 23 and (3) in Pict. 24) should push the
needle in a way, that a distance of 0 to 0.05 mm exists between grab
top and needle.