Each state has specific coverages and limits available, but Uninsured Motorist Property Damage coverage typically covers damage to the insured vehicle in an accident caused by a driver who has no insurance coverage.
Each state has different limiations to determine the limits. For example in California if you don't have Collision coverage, Uninsured Motorist Property Damage coverage pays up to $3,500 for repairs to the insured car. If you have Collision coverage, Uninsured Motorist Property Damage coverage pays your Collision deductible.
As you can see, Uninsured Motorist Property Damage alone is not enough to cover all potential car repair/replacement costs and it should not be considered a replacement for Collision coverage. It only applies if you are involved in an accident caused by a driver without insurance coverage. Also, it doesn't handle all incidents that aren't covered by Collision (Other Than Collision or Comprehensive).