There are a total of 13 pairs of knitting needles.  
The sizes are 11, 10 1/2, 9, 8, 7, 6, 5, 4, 3 1/2, 3, 2 (long plastic), 2 (short aluminum) and 1.  
The size 3 1/2  are about 1 1/2" longer than the others. 
I hope I haven't totally confused you.