Explorer II was a pistol version of the AR-7.
It resembled a Broomhandle Mauser.
The receiver had a built-in pistol grip with no provision for the rifle stock (the internal parts are interchangeable between rifle and pistol).
The rear sight of the pistol was an open notch adjustable for windage and elevation.
The Explorer II front sight was integral with the barrel shell and was not adjustable.
The magazine well in front of the trigger guard would accept any magazine designed for the rifle.
A spare 8-round magazine could be carried inside the grip.
The most common barrel was six inches.
 Optional barrel lengths included eight and ten inches.
Explorer II was a pistol version of the AR-7. It resembled a Broomhandle Mauser. The receiver had a built-in pistol grip with no provision for the rifle stock (the internal parts are interchangeable between rifle and pistol). The rear sight of the pistol was an open notch adjustable for windage and elevation. The Explorer II front sight was integral with the barrel shell and was not adjustable. The magazine well in front of the trigger guard would accept any magazine designed for the rifle. A spare 8-round magazine could be carried inside the grip. The most common barrel was six inches.  Optional barrel lengths included eight and ten inches.
ArmaLite AR-7