No. 1 is a pale speckled blue button with a flower design.
No. 2 has a rather crude look combining a dull green and gold.
No. 3 has a high gloss and an abstract blue pattern.
No. 4 combines black and taupe in a wavy pattern.
The first one has a self shank while the other three are sew through. Note that No. 2 has three holes which is a little different.