- 
        
          51 Button and Switches  - 
        
          52 battery  - 
        
          53 cables  
- 
        
          54 capacitors  - 
        
          55 Connectors  - 
        
          56 Data Loggers  
- 
        
          5A LCD and LEDS  - 
        
          5B LEDs and illumination  - 
        
          5C logic  
- 
        
          5D Magnets  - 
        
          5E Memory and Cards  - 
        
          5F Oscillators  
- 
        
          5G Potentiometer  - 
        
          5H power  - 
         
          5I Resistors  
- 
        
          5J RTC (Real Time Clock)  - 
       
          5K Transistors  - 
        
          5L Lasers