ACS PAWS 16T+ BMX Bicycle Single Speed Freewheel Tool (4 prong)
ACS BMX (single speed) PAWS Freewheel Removal Tool
4 prong mating, which is the most common freewheel interface (but always check yours first... there are several different types depending on brand and age of the freewheel).
Typically if your freewheel is single speed and 16 teeth or larger, this is the tool it uses. This is the correct tool for the ACS PAWS series of freewheels that are 16T and larger.
This will NOT fit ACS Crossfire freewheels.
This will NOT work with Shimano MX-30 freewheels.
The hex portion is 24mm and it can be used with a wrench or with a vice (I actually use an impact wrench with mine - works like a charm).