Unless rubbing your nipples is part of your job, anyway.. Andractim testosterone gel is a topical gel, which comes in a tube, containing 80x 25mg doses of DHT. Absorption rate is going to be similar to testosterone gel, or roughly 10%, so youre applying 2.5mgs of pure DHT to your nips every time you use this stuff.
Servos are also used in in-line manufacturing, where high repetition yet precise work is necessary. Of course, you don't have to know how a servo works to use one, but as with most electronics, the more you understand, the more doors open for expanded projects and projects' capabilities.
A typical Servo looks like a rectangular box with a motor shaft coming out of one end and a connector with three wires out of the other end. The three wires are the power, Control, and Ground. Servos work with voltages between 4 and 6 volts. The control line is used to position the servo. The servo motor comes in different sizes, which affect the overall size of the servo. The gears of a servo vary from servo to servo. Inexpensive servos have plastic gears, and more expensive servos have metal gears which are much more rugged but wear faster.