Chevrolet 2003 Blazer Owner's Manual page 332

Removing the Wheel Cover
The tools you'll be using include the jack (A) and wheel
wrench (B). Your vehicle may also have an optional
hub cap removal tool.
Position the chisel end of your wheel wrench, or the hub
cap removal tool (if equipped), in the notch of the hub
cap and pry off the hub cap.
Some of the molded plastic hub caps have imitation
wheel nuts molded into them. The wheel wrench won't
fit these imitation nuts, so don't try to remove them
with the socket end of the wheel wrench.
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