If you have a swirl post in your top loader, such as a Whirlpool top loader, that style of agitator has thinner and sharper edges and those edges tend to wear out fabrics more quickly than the agitator shown in the Speed Queen video.
Piping is a trim or edging formed by sewing a thin strip of folded fabric — typically bias binding — into a narrow tube and attaching it to the edgeof a piece offabric.