Product Overview

The Ether-3D KUNA SXR Handguard is a newly designed extended handguard for the Springfield KUNA, providing additional forward handguard length and accessory mounting space while maintaining a lightweight, integrated profile.

The SXR’s overall styling was inspired by the distinctive profile of the Geissele Automatics MK4 Super Modular Rail, while being independently designed by Ether-3D specifically for the Springfield KUNA platform. The SXR is not a reproduction or replica of the MK4 and incorporates its own dimensions, mounting system, construction, and features tailored specifically to the KUNA.

At approximately 7.25 inches in overall length, the SXR extends approximately 3.5 inches beyond the factory receiver, providing additional support-hand space and usable rail length while maintaining a compact overall profile.

The design features a continuous MIL-STD-1913 Picatinny top rail along with integrated M-LOK mounting slots on both sides and the bottom for compatible accessories.

Manufactured from carbon-fiber reinforced polymer, the handguard combines lightweight construction with rigidity and reduced heat transfer compared with traditional metal handguards. Each SXR handguard is precision 3D printed in the USA with a clean carbon-fiber appearance.

Key Features

  • Approximately 7.25-inch overall length
  • Extends approximately 3.5 inches beyond the factory receiver
  • SXR modular rail design
  • Styling inspired by the Geissele Automatics MK4 Super Modular Rail
  • Independently designed by Ether-3D specifically for the Springfield KUNA
  • Continuous MIL-STD-1913 Picatinny top rail
  • Integrated M-LOK slots on both sides and bottom
  • Compatible with the factory front sight
  • Designed to accommodate suppressors up to approximately 1.65 inches in diameter
  • Durable carbon-fiber reinforced polymer construction
  • Reduced heat transfer compared with traditional metal handguards
  • No cutting, drilling, or permanent firearm modifications required
  • Precision 3D printed in the USA

Specifications

Specification Details
Product Line Ether-3D KUNA SXR
Material Carbon Fiber Reinforced Polymer
Compatibility Springfield KUNA
Overall Length Approx. 7.25 in.
Extension Beyond Receiver Approx. 3.5 in.
Height Approx. 3.1 in.
Width Approx. 2.2 in.
Weight TBD
Top Rail MIL-STD-1913 Picatinny
Accessory Mounting M-LOK – Sides & Bottom
Max. Suppressor Diameter Approx. 1.65 in.
Manufacturing Method Additive Manufacturing / 3D Printed
Manufacturer Ether-3D
Country of Manufacture USA

Compatibility

Designed specifically for the Springfield KUNA.

The SXR incorporates a continuous MIL-STD-1913 Picatinny top rail that aligns with the factory rail while maintaining compatibility with the factory front sight.

Integrated M-LOK slots are located on both sides and the bottom of the handguard for mounting compatible accessories.

The internal dimensions are designed to accommodate compatible suppressors measuring up to approximately 1.65 inches in diameter.

Depending on suppressor diameter and accessory placement, shorter M-LOK screws may be required to maintain proper internal clearance.

Always verify adequate clearance between the suppressor, M-LOK hardware, and inside of the handguard before use.

What's Included

  • 1 × Ether-3D KUNA SXR Handguard

Mounting hardware, firearm, suppressor, optics, lights, and other accessories shown in product photos are not included.

Important Information

Each handguard is individually produced using carbon-fiber reinforced polymer and additive manufacturing. Minor variations in surface texture or layer appearance are normal characteristics of the manufacturing process and do not necessarily indicate a defect.

M-LOK Torque

Maximum recommended torque: 11–13 in-lbs

Do not exceed the recommended torque when installing M-LOK accessories. Excessive torque can permanently damage polymer M-LOK mounting slots.

Use a torque wrench whenever possible and verify that all M-LOK T-nuts rotate completely into the locked position before tightening.

Suppressor & Heat Safety

This handguard should only be used with a compatible suppressor or approved muzzle extension that extends beyond the front of the handguard.

Do not fire with the muzzle terminating inside the handguard.

Before use, verify adequate clearance between the suppressor and the inside of the handguard and ensure M-LOK screws or other accessory hardware do not contact the suppressor.

Carbon-fiber reinforced polymer provides reduced heat transfer compared with metal; however, it remains a polymer component. Repeated rapid fire, prolonged firing without adequate cooling, or other unusually aggressive firing schedules can generate temperatures beyond the material's intended operating range.

Allow the suppressor and handguard to cool periodically during extended use.

The heat deflection temperature (HDT) of PETG is typically between 65°C and 75°C (149°F to 167°F).

PA6-CF (carbon fiber-reinforced nylon 6) has a heat deflection temperature ranging from approximately 173°C to 196°C (343.4°F to 384.8°F) at high load.

Always verify proper installation, fitment, clearance, and secure attachment before use.

Design Inspiration & Trademark Notice

The Ether-3D KUNA SXR Handguard was independently designed by Ether-3D specifically for the Springfield KUNA. Its overall styling was inspired by the Geissele Automatics MK4 Super Modular Rail.

The KUNA SXR is not a reproduction or replica of the Geissele MK4 and features its own dimensions, construction, mounting arrangement, and KUNA-specific design.

Ether-3D is not affiliated with, endorsed by, or sponsored by Geissele Automatics or Springfield Armory. Geissele, MK4, Springfield Armory, and KUNA are trademarks of their respective owners.

Manufactured by Ether-3D in Southern Indiana, USA.

Precision • Performance • Printed