Side-folding triangle buttstock set made in Bulgaria. These sets meet all military specifications and were produced under contract for the Bulgarian military. The buttstock set includes everything you need including rivets. The set consists of the sheet-metal buttstock, machined rear trunnion, latch mechanism for the trunnion, and latch for the front of the receiver that secures the buttstock in the folded position. All necessary springs and pins are included. Very nice welds and no tool marks. Pivot pin is standard military 5.5mm.