The HW section is a special case of an Install section. It is the only type of INF file section that allows entries to be made to the Enum branch of the registry. The HW section is used to add or delete device-related, driver-independent information from the registry.
[install-section-name.HW] AddReg=add-registry-section[,add-registry-section]... DelReg=del-registry-section[,del-registry-section]...
The only items that can appear in a HW section are AddReg and DelReg. Using the HKR designation in an AddReg item adds registry entries into the registry Enum branch and using the HKR designation in a DelReg item deletes entries from the registry Enum branch. HW sections are useful for installing multifunction devices.