The BT Delta Upgrade Kit will take your marker from a stock BT-4 and transform it into a complete BT Delta marker, with its authentic submachine gun styling.
Detla Upgrade Kit Includes:
- 9” Precision barrel and shroud with Apex ready tip
- Adjustable Collapsible stock
- Picatinny mounted magazine
- Picatinny Mount Clamp Elbow with Shroud
- Fits any BT-4 model marker
- Authentic SMG styling