The pinnacle of zombie armor, a vest provides bite protection in the shoulder chest and back regions. They also double as sidearms and ammo carriers and can be modified to suit your needs. That and they look incredibly badass.
Face and Eyeshields
The last thing you want is undead brain matter getting in your mouth or eyes. Not to mention when the bullets are flying it doesn't hurt to have some good shooting glasses.
Holsters and Platforms
Know where you sidearm is at all times. It will save you when your main zombie killing device fails. The preferred carry method of zombie slayers everywhere is and always has been the drop leg platform.
Your fingers are a delicacy to a hungry zombie. While not absolute protection, gloves go a long way in keeping your trigger finger where it belongs, attached to your hands!