You often use a round awl as a precursor to your sewing needle. When hand sewing, it can be very important to minimize the hole created by your round awl. It’s usually the size of your sewing needle.
This round awl will match the size of your needle perfectly because that’s what it uses! This awl allows you to use your own sewing needles as the awl blade, making them easy to replace. Use a new needle or one that’s ready to retire from sewing but still usable as an awl blade.