Adam Lanza brought three weapons inside Sandy Hook Elementary school on December 14 and left a fourth in his car, police said. Those weapons were a Bushmaster AR-15 rifle and two handguns -- a Glock 10 mm and a Sig Sauer 9 mm. In the car he left a shotgun, about which police have offered no details. Lanza used one of the handguns to take his own life, although police haven't said whether the gun was the Glock or the Sig Sauer. In fact many details remain unknown about the weapons Lanza used that day to kill 20 children, his own mother, six other adults and then himself. Here's what is known so far:
@highlight
Police: Newtown, Connecticut, gunman came to school grounds with four weapons
@highlight
Guns included a shotgun, an AR-15 rifle,  a Glock 10 mm and a Sig Sauer 9 mm
@highlight
Lanza used numerous 30-round magazines to load his rifle, police say
@highlight
The shotgun was found in Lanza's parked car, police say
Bushmaster AR-15
The original M-16 patent ran out years ago, and now the @placeholder is manufactured by several gunmakers.
Bushmaster AR-15
An @placeholder is usually capable of firing a rate of 45 rounds per minute in semiautomatic mode.
Glock
Glock
But Glock lists two types on its website, including the Glock 20 and @placeholder.
Glock
Glock
The Glock 20 measures nearly 8 ¼ inches long and weighs about 2 ½ pounds when loaded, according to @placeholder's website.
Sig Sauer
Sig Sauer
Sig Sauer
The other handgun police said Lanza had with him during the school massacre was a @placeholder.
Adam Lanza
Lanza
Lanza
Lanza
Lanza
Like the Glock, @placeholder's Sig Sauer also allowed a high-capacity magazine, Vance said.
Sig Sauer
Sig Sauer
Sig Sauer
Lanza used "multiple magazines" that are widely available to feed ammunition to the @placeholder, Vance said.
Sig Sauer
Sig Sauer
Sig Sauer
@placeholder makes 9 mm pistol magazines with a maximum capacity of 20 bullets.