Product review (5 stars): Frigidaire Selector Knob
I have had the washer and dryer since 2004.  My roommate (male) started washing our clothes.  Off goes the knobs on the dryer.  I searched high and low to find them, and to my amazement, I found them on Amazon.com.  Even then, I had to check to see if I was ordering the right knobs.  I did check the reviews that mentioned there were two types.  I went with my gut, got the right ones, and I am extremely happy.  Though I wish Amazon had listed the two types separately.