The gun that fired accidentally, killing a 10-year-old Keegan Swinney Tuesday, was a Remington Airmaster .177, El Dorado County Sheriff's officials reported Thursday.
Swinney and some friends were shooting the gun in a backyard before he was accidentally shot by one of the boys who was cradling the weapon in a non-shooting position.
The Remington Airmaster is shown as available for $79.96 on Walmart.com to buyers over 18 years old.
It fires BBs or non-spherical metallic pellets at more than 700 feet per second using a pneumatic pump.
Customer reviews were enthusiastic about its power and usefulness for killing squirrels.
The pellets used in this type of gun are not the plastic ones used in airsoft guns, which are intended for game play.
Those are said typically to produce welts on exposed skin, but do not break the skin.
The Remington company's website identifies the Airmaster as a licensed product made by another manufacturer.
Walmart.com's website includes a warning to California purchasers that the gun "may be mistaken for a firearm by law enforcement officers."