Most guys use a 1/16, but lots also use 1/32 and 1/8. The first thing you need to know is when they add a collar to a jig head, they don't change the size of the head so if that is a true or close to 1/16 then the ones with a collar are heavier than 1/16 even though it says 1/16!
Size of jig head many times will come down to how deep a guy fishes, in spring and fall I use 1/32 and in summer fishing 14 to 25' down I use 1/8 and 1/4.
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