These are sensors which have their sensing area formed in a ring
 and sensing occurs when a metallic mass enters this ring. They are
 particularly suitable for sensing, counting and checking small metal
 parts: screws, nuts washers etc. or for similar applications.
 
 -They are supplied with internal diameter
  5-12-15-22-25-30- 44-63-100 mm.
 -NAMUR types from 5 ÷ 24 Vdc
 -NAMUR EX types
 -Amplified 3 and 4 wire types NPN or PNP from 10 ÷ 30 Vdc
  SIA25 totally screened against mutual interference
 -Led incorporated
 -Max. output current 200 mA
 -Types with retained impulse 100 ms
  All types are available with cable or plug for connector