Firearm purchases require a background check and must be picked up in person by the purchaserSBR transfers will not be accepted
 
The Colt Mustang Mark IV Series 80 is a compact, single-action .380 ACP pocket pistol, commonly featuring a 2.75-inch barrel, 5.5-inch total length, and a 6-round magazine capacity. Designed like a scaled-down 1911, it is noted for its lightweight (around 12.5–18.5 oz depending on frame material) and reliability, popular for concealed carry. 
Colt Mustang Mark IV Series 80 Key Specifications:
Caliber: .380 ACP
Action: Semi-automatic, Series 80 firing system
Barrel Length: 2.75 inches
Overall Length: 5.5 inches
Capacity: 6+1 rounds (standard)
Weight: ~12.5 oz (Pocketlite) to 18.5 oz (Steel Frame)
Frame Material: Aluminum alloy (Pocketlite) or Steel (Blued/Stainless)
Sights: Fixed square notch rear/blade front
Trigger: Single-action 
Variants:
Mustang Pocketlite: Aluminum alloy frame, lower weight (~12.5 oz).
Mustang Plus II: Longer grip frame, 7+1 or 8+1 round capacity, 6-inch total length.
Original Mustang: Steel frame, higher weight. 
Wikipedia +2
It features a locked-breech system, which helps reduce felt recoil compared to blowback .380s.