When I started to learn arduino, I found that it waste a lot time by repeating connect LED and it's resistor.
So, I try to solder the LED (please refer to photo) and the resistor to pins.
The outcome is very effective, not only the blocks can be used in arduino, but it can use as battery tester (positive or negative), and testing for the effect of different LED color (for flashing effect).
Then I connect the IRF510 in the same way, but I solder two set of pins for easy standing upright on the breadboard. The three letters on the IRF510 represent :- (the green terminals connected is the power output)
P - connecting to arduino (control)
+ - connecting to Positive of external power source
- - connecting to GND of external power source
But the way, the IRF510 block can directly use Dupont Line, because the two set of pins allow it to connect to the GND of Arduino and power supply easily.
It can easily reuse and save a lot of money, sure u can make more blocks.