There are two basic types of ball point pens: disposable and refillable; disposable pens are chiefly made of plastic throughout and discarded when the ink is consumed; refillable pens are metal and some plastic and tend to be much higher in price.
There are two basic types of ball point pens: disposable and refillable. Disposable pens are chiefly made of plastic throughout. Disposable pens are chiefly discarded. The ink is consumed. Refillable pens are metal. Refillable pens are some plastic. Refillable pens tend to be much higher in price.