Dubro 4-40 Threaded Inserts RC Aircraft Spare Part (4 Pack) - DUB391

The Dubro DUB391 4-40 threaded inserts are metal hardware components used in RC aircraft construction and repair to provide strong, reliable thread anchoring in balsa, foam, or composite airframe materials. Sold in a pack of four, these 4-40 sized inserts are a practical solution for builders who need secure, repeatable fastening points in areas subject to vibration or repeated assembly and disassembly. Dubro is a well-established name in RC aircraft hardware, and the 391 threaded inserts are a standard shop item for scratch builders and kit builders alike.

Key Features

• 4-40 thread size suits a wide range of small RC aircraft hardware including control horns, servo mounts, and hinges
• Metal construction provides durable thread engagement compared to tapping directly into soft airframe materials
• Designed for installation into balsa, foam, or lightweight composite structures
• Pack of four gives you a useful quantity for a single build or for keeping on the workbench as stock
• Compatible with standard 4-40 screws widely used across RC aircraft kits and accessories

What's Included

• 4 x Dubro 4-40 threaded metal inserts

What You Need

• Appropriate installation tool or drill bit sized for your airframe material
• 4-40 screws (sold separately) to complete the fastened assembly
• Adhesive suitable for your airframe material if bonding the inserts in place