Losi Set Screws 4mm 5mm Grub Screws 6 Each Z-LOSA6250

• Brand: Losi
• Model number: Z-LOSA6250
• Product type: Set screws
• Screw sizes included: 4mm and 5mm
• Quantity of 4mm screws: 6 pieces
• Quantity of 5mm screws: 6 pieces
• Total quantity: 12 screws
• Fastener type: Grub screws / Set screws
• Application: Losi RC models

Overview

The LOS Set Screws, 4mm and 5mm (6 each) Z-LOSA6250 is an essential spare parts pack designed specifically for Losi RC models. Whether you're maintaining your RC car UK collection, performing routine maintenance on your ready to run RC vehicle, or building a competition-grade model, these precision set screws are an indispensable addition to your pit box. Set screws, also known as grub screws, are fundamental fastening components used throughout RC vehicles to secure gears, pulleys, shafts and other critical components in place, preventing unwanted movement and ensuring reliable performance during high-speed runs and challenging off-road conditions.

This pack includes 6 pieces each of 4mm and 5mm set screws, giving you a total of 12 fasteners to cover multiple assembly points or replacements across your Losi models. Set screws are the backbone of RC car assembly and maintenance, holding together the drivetrain components, motor mounts, and transmission elements that make your vehicle perform at its best. For any RC enthusiast in the UK operating Losi vehicles, having spare set screws on hand is simply good maintenance practice and ensures you're never left stranded at the track or bash spot due to a missing or stripped fastener.

These screws are manufactured to Losi's exacting standards and are the genuine spare parts you need to keep your Losi RC models running smoothly. Whether you're a competitive racer fine-tuning your vehicle, a weekend basher pushing your model to its limits, or someone just discovering the world of RC hobbies for the first time, understanding the importance of quality fasteners like these set screws is crucial to long-term reliability and performance.

Key Features

• Two sizes included — This pack provides both 4mm and 5mm set screws, giving you flexibility to service multiple Losi models and different assembly points that may require different fastener sizes for proper fit and secure retention.
• 6 pieces of each size — With half a dozen of each diameter, you have enough fasteners to service multiple vehicle rebuild points, replace worn or stripped screws, or stock your spares box for future maintenance sessions without needing to order repeatedly.
• Genuine Losi manufacture — These are authentic Losi spare parts engineered to the same specifications as the original fasteners installed in Losi vehicles, ensuring compatibility and reliability across the entire Losi model range.
• Essential maintenance item — Set screws are critical fastening components used throughout RC vehicles to hold gears, shafts, pulleys and drivetrain elements securely in place, preventing loss of performance or mechanical failure during operation.
• Compact and portable — This convenient pack is small enough to carry in your pit bag or toolbox, making it easy to have spare set screws available whenever you need them at the track or field.

Technical Performance

Set screws are precision fasteners engineered to provide secure, reliable clamping force on cylindrical components without requiring a drilled hole through the shaft or component. The 4mm and 5mm sizes included in this pack are standard specifications across numerous Losi RC models, from buggies and trucks to crawlers and competition vehicles. These fasteners are manufactured to exacting tolerances to ensure smooth insertion, secure holding power, and resistance to vibration-induced loosening during high-speed operation and aggressive driving. The hardened steel construction provides durability and longevity, resisting stripping and deformation even under the stresses of competitive racing or hard bashing. Whether you're working on transmission shafts, motor mounts, or gear retention points, having genuine Losi set screws in your spares collection ensures you maintain the engineering integrity of your models. The precise threading and sizing prevents cross-threading and allows for controlled tightening without over-torquing, which could damage the host component. These are the same specification fasteners that Losi engineers specify for their factory builds and competition kits.

What's in the Box

• 6 x 4mm set screws
• 6 x 5mm set screws

Frequently Asked Questions

• What are set screws used for in RC cars? — Set screws, also called grub screws, are used to secure cylindrical components like gears, motor shafts, and pulleys firmly onto axles and drive shafts. They apply clamping pressure perpendicular to the shaft without requiring a hole through the shaft itself, making them ideal for securing drivetrain components that need to stay locked in place during operation.
• Why would I need replacement set screws? — During normal operation and maintenance of your RC car UK model, set screws can become loose from vibration, may need to be removed for gear changes or component upgrades, or can become stripped or damaged if over-tightened or if a component is removed and reinstalled multiple times. Having spare set screws ensures you can quickly service your vehicle without waiting for replacement parts.
• Are these genuine Losi parts? — Yes, the LOS Set Screws Z-LOSA6250 are authentic Losi manufactured spare parts engineered to the same specifications as original equipment, ensuring perfect compatibility with Losi RC models and reliable performance.
• What Losi models use these set screws? — These sizes are standard across the Losi range, including buggies, trucks, short-course vehicles, and competition models. Check your specific vehicle's manual or parts diagram to confirm which screw sizes are used at different assembly points on your model.
• How do I install set screws correctly? — Set screws should be inserted into the threaded socket in the component housing and tightened gradually until the screw point contacts the shaft and applies clamping pressure. Do not over-tighten, as this can strip the threads or damage the shaft. Use an appropriate hex key and apply firm but controlled pressure.

Why Buy from RC Model Shop?

RC Model Shop is a trusted UK RC retailer and authorised dealer for all the brands we stock, including Traxxas, ARRMA, Losi, FTX, Hobbywing, Spektrum and more. Based in Walsall, we have a physical store where customers are welcome to come in, view products and purchase in store. Whether you are a seasoned competitor, a weekend basher, or just discovering the world of RC for the first time, our team of experienced RC enthusiasts is here to help you find the perfect setup and provide ongoing support. Order the LOS Set Screws, 4mm and 5mm (6 each) Z-LOSA6250 today with confidence, knowing you are buying from an authorised retailer with genuine products, expert knowledge and a commitment to customer satisfaction. Shop online or visit us in Walsall — we look forward to helping you get the most out of your RC experience.

We want to make sure your delivery goes smoothly, so here are some important details about our service:

• For orders above £120, we offer delivery to most mainland UK addresses. For orders under £120, we can still deliver to Northern Ireland and the outlying isles, as long as the item can be sent by Royal Mail, weighs less than 30kg, and fits within 61cm × 46cm × 46cm. Some highland and remote areas may carry an extra delivery charge as couriers often apply surcharges in these locations. If you live in one of these areas, feel free to contact us before ordering so we can confirm the delivery options and costs for you.
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