The pistol may have a condition where the trigger bar pin could damage the lower trigger and affect the functionality of the drop safety feature. As a result, the pistol could potentially discharge if dropped, according to the alert.
The gun maker advised consumers to inspect the firearm immediately and either repair the issue themselves or bring the weapon to an M&P certified armorer or ship it to the company. View an S&W video showing the inspection procedure here.
The safety alert applies to all M&P Shield pistols produced before Aug. 19. Owners can check to see if their pistol is affected by visiting MPShieldSafetyAlert.com.