Messi and Paoloni ExtraFlex Bury 400 – 50 Ω Coaxial Cable The Messi and Paoloni ExtraFlex Bury 400 is a heavy-duty 50 Ω coaxial cable specifically designed for permanent underground and outdoor amateur radio installations. Built for extreme durability, this cable combines low-loss performance with exceptional resistance to environmental stress. Engineered for reliable RF performance across HF, VHF and UHF bands, ExtraFlex Bury 400 features a construction optimised for long-term burial and exposure to moisture. Its design makes it ideal for installations where the cable must be routed underground without additional conduit. Totally waterproof and suitable for direct burial, ExtraFlex Bury 400 is well suited to permanent antenna systems where long service life and dependable performance are critical. Available either cut to length per metre or supplied as a 100 metre drum, allowing you to choose the option that best suits your installation requirements. Key Features 50 Ω coaxial cable designed for underground and outdoor installations Extra-flexible construction with low-loss RF performance Totally waterproof and suitable for direct burial Highly resistant to moisture and environmental conditions Ideal for permanent, long-term antenna installations Available per metre or as a 100 metre drum Ideal For Buried coaxial cable runs between shack and antenna Permanent HF, VHF and UHF antenna installations Outdoor installations where maximum durability is required When your installation demands a coaxial cable that can be buried with confidence, the Messi and Paoloni ExtraFlex Bury 400 delivers a robust, professional-grade solution you can rely on. Moonraker – the Ham Radio Superstore. Messi and Paoloni Other RF Coax Cable Solutions Explore more Messi and Paoloni coax options below. Each cable is designed for a specific type of installation, from lightweight portable setups to low-loss base station feedlines and direct-burial outdoor runs. Airborne 5 – A lightweight 5 mm coax designed for outdoor use where flexibility and durability are essential. Hyperflex 5 – A compact, highly flexible 5.4 mm PVC jacket coax, ideal for tight routing and portable or mobile use. Ultraflex 7 – A popular 7.3 mm general-purpose low-loss coax with a flexible PVC jacket for fixed, portable and mobile stations. POTA-FLEX 7 – A rugged outdoor and portable cable in high-visibility yellow, built for repeated deployment and harsh handling. Extraflex Bury 7 – A 7.3 mm waterproof coax designed specifically for direct burial and underground runs. Airborne 10 – A heavy-duty outdoor coax for permanent installations, offering excellent durability and weather resistance. Broad Pro 50C LSZH – A safety-focused coax with an LSZH jacket for indoor and public installations. Ultraflex 10C (Competition) – A competition-grade flexible low-loss coax for high-performance base and contest stations. Hyperflex 10 – A large-diameter flexible coax offering low-loss performance with easier routing. Extraflex Bury 10 – A heavy-duty direct-burial coax for permanent underground outdoor installations. Hyperflex 13 – A very low-loss feedline for demanding base stations and long cable runs. Comparison (tap on the dimensions to the right to view further details) Airborne 5 5.0 mm • 9.4 dB Diameter5.0 mm Loss9.4 dB per 100 m at 100 MHz Outer JacketShielded Polyethylene Outer BraidReactive Braid Inner CoreSolid Copper 1.13 mm Hyperflex 5 5.4 mm • 8.0 dB Diameter5.4 mm Loss8.0 dB per 100 m at 100 MHz Outer JacketPVC Outer BraidReactive Braid Inner CoreCopper Wires 1.4 mm Ultraflex 7 7.3 mm • 5.8 dB Diameter7.3 mm Loss5.8 dB per 100 m at 100 MHz Outer JacketPVC Outer BraidReactive Braid Inner CoreCopper Wires 1.9 mm POTA-FLEX 7 7.65 mm • 5.8 dB Diameter7.65 mm Loss5.8 dB per 100 m at 100 MHz Outer JacketShielded Polyethylene (Yellow) Outer BraidTwin Braid Inner CoreCopper Wires 1.9 mm Extraflex Bury 7 7.3 mm • 5.8 dB Diameter7.3 mm Loss5.8 dB per 100 m at 100 MHz Outer JacketShielded Polyethylene Outer BraidReactive Braid Inner CoreCopper Wires 1.9 mm Airborne 10 10.3 mm • 3.5 dB Diameter10.3 mm Loss3.5 dB per 100 m at 100 MHz Outer JacketShielded Polyethylene Outer BraidReactive Braid Inner CoreSolid Copper 2.78 mm Broad Pro 50C LSZH 10.3 mm • 3.6 dB Diameter10.3 mm Loss3.6 dB per 100 m at 100 MHz Outer JacketLSZH Outer BraidReactive Braid Inner CoreSolid Copper 2.76 mm Ultraflex 10C 10.3 mm • 3.9 dB Diameter10.3 mm Loss3.9 dB per 100 m at 100 MHz Outer JacketPVC Outer BraidReactive Braid Inner CoreCopper Wires 2.9 mm Hyperflex 10 10.3 mm • 3.9 dB Diameter10.3 mm Loss3.9 dB per 100 m at 100 MHz Outer JacketPVC Outer BraidReactive Braid Inner CoreCopper Wires 2.9 mm Extraflex Bury 10 10.3 mm • 3.9 dB Diameter10.3 mm Loss3.9 dB per 100 m at 100 MHz Outer JacketShielded Polyethylene Outer BraidReactive Braid Inner CoreCopper Wires 2.9 mm Hyperflex 13 12.7 mm • 2.8 dB Diameter12.7 mm Loss2.8 dB per 100 m at 100 MHz Outer JacketPVC Outer BraidReactive Braid Inner CoreCopper Wires 3.8 mm Cable Diameter (mm) Loss (dB per 100 m at 100 MHz) Outer Jacket Outer Braid Inner Core Airborne 5 5.0 9.4 Shielded Polyethylene Reactive Braid Solid Copper 1.13 mm Hyperflex 5 5.4 8.0 PVC Reactive Braid Copper Wires 1.4 mm Ultraflex 7 7.3 5.8 PVC Reactive Braid Copper Wires 1.9 mm POTA-FLEX 7 7.65 5.8 Shielded Polyethylene (Yellow) Twin Braid Copper Wires 1.9 mm Extraflex Bury 7 7.3 5.8 Shielded Polyethylene Reactive Braid Copper Wires 1.9 mm Airborne 10 10.3 3.5 Shielded Polyethylene Reactive Braid Solid Copper 2.78 mm Broad Pro 50C LSZH 10.3 3.6 LSZH Reactive Braid Solid Copper 2.76 mm Ultraflex 10C 10.3 3.9 PVC Reactive Braid Copper Wires 2.9 mm Hyperflex 10 10.3 3.9 PVC Reactive Braid Copper Wires 2.9 mm Extraflex Bury 10 10.3 3.9 Shielded Polyethylene Reactive Braid Copper Wires 2.9 mm Hyperflex 13 12.7 2.8 PVC Reactive Braid Copper Wires 3.8 mm