I'll check it soon. I think it's better to use 'K' instead of 'k' because of misunderstanding possibility.
from man dd:
BLOCKS and BYTES may be followed by the following multiplicative suffixes: c =1, w =2, b =512, kB =1000, K =1024, MB =1000*1000, M =1024*1024, xM =M GB =1000*1000*1000, G...