Designation  | 
          Signal  | 
          Description  | 
        
        
          |  1.Mounting  hole  | 
          T2  | 
           Φ22mm/Φ25mm | 
        
        
          T3  | 
           Φ30mm | 
        
        
          |  2.Type | 
          KL  | 
           Long head  | 
        
        
          KM  | 
           Mushroom head  | 
        
        
          |  3.Shape | 
          R  | 
           Round | 
        
        
          S  | 
           Square | 
        
        
          |  4.Movement  way  | 
          1  | 
           1. Key Return Type  | 
        
        
           1) It can't be pressed down when it's in still.  
             2) It will become return type push button after being  pressed down when the key is turned right.  | 
        
        
          2  | 
            2. Key Chain Type  | 
        
        
           1) Press it down when it¨s in still and it'll become  chain type push button. 
             2) It will return after being pressed down when the  key isturned right.  | 
        
        
          3  | 
            3. Key Fixing Type  | 
        
        
           1) It can't be pressed down when it's in still. 
           2) It can be pressed down when the key is turned  right.It will be further fixed after the key is turned  left. 
           3) It will return when the key is turned right.  | 
        
        
          4  | 
           4. Key Chain Return Type  | 
        
        
           1) It will become chain type after being pressed  down when the key is in still and will return when  the key is turned right. 
             2) It will become return push button when the key is  turned right and drawn out.  | 
        
        
          |  5.Key  withdrawable  | 
          1  | 
           It may be drawn out both in stillness and being  turned right.  | 
        
        
          2  | 
            It may be drawn out in stillness.  | 
        
        
          6.No.of contact 
            Blocks fitted   | 
          1-3  | 
           1-3 
           | 
        
        
           7.Type of  contact 
             Blocks fitted  | 
          A  | 
           1A | 
        
        
          B  | 
           1B | 
        
        
          C  | 
           1A1B |