Question: what is a 3mm guard?
Answer: #1 haircuts guards are often about 1/8th of an inch or 3mm long while the #1.5 are 3/16” or 4.8mm. These are the numbers you ask for when you're looking for a perfect buzz cut. ... Also, just like the #0 haircut, there will be a degree of scalp exposure with #1 haircuts.