This is a Dubro DUB884 Heavy Duty 4-40 Ball Link.

The DU-BRO Heavy Duty 4-40 Ball Link is a strong, simple, and reliable solution for creating smooth control movement in your RC model. Whether you are flying a larger sport plane, a scale aircraft, or an aerobatic model, this ball link helps your control system stay tight, accurate, and free-moving.

This 3-piece set includes everything you need for one complete assembly:

1 heavy-duty 4-40 threaded ball

1 self-threading nylon socket

1 4-40 lock nut

The ball provides a pivot point that allows the linkage to move smoothly and reduces binding. This helps improve the feel and precision of your elevator, rudder, aileron, or throttle control. Because the socket is self-threading, it attaches easily to any 4-40 pushrod, making installation quick and beginner-friendly.

Even though this ball link is made for heavy-duty use, it weighs only 2 grams, so it adds almost no extra weight to your model. This makes it perfect for larger airplanes that require strong hardware but still benefit from keeping the airframe light and responsive.

The DU-BRO Heavy Duty 4-40 Ball Link is ideal for upgrading older linkage systems or building new models with smoother, more accurate controls. It offers a secure connection, easy installation, and dependable long-term performance.

Proudly Made in the USA, this ball link gives you the strength, reliability, and smooth operation that DU-BRO products are known for—helping your aircraft fly better and respond more cleanly to every control input.

e of two aileron horn wire ball links.

Combined shipping: I am happy to offer a combined shipping discount. Just add all the items you want into your shopping cart (International Buyers may have to log onto the ebay US website to do this), then go into your shopping cart and click on the "Request total from Seller" link. We will pull, package, and weight your order and then send you a revised invoice with the correct shipping. All items must be paid for with a single payment to qualify for combined shipping discounts. 

Note: ebay's mobile site and mobile app may not show you the "request shipping" option. If you do not see this option in your cart, scroll down to the bottom of the page and click on "classic site". This will give you access to the full website which will show the link. Similarly, when you go to pay using the combined invoice, you must also be on the full website.

Note: Additional shipping charges may apply to heavy items shipping to Hawaii, Alaska and US Possessions (Puerto Rico, American Samoa, etc). This is because within the continental 48 states we can ship via FedEx ground which is inexpensive. Outside of that area it must go Airmail. Hazardous materials cannot ship outside the contiguous 48 states.

Expected Delivery Times within the 48 Contiguous states:

Powered by SixBit's eCommerce Solution