- Shenzhen-based Star-Navi's XRAM-C Series radar-absorbing coatings claim at least 3.0 dB radar reflection loss across 8–12 GHz, applied at 0.40–0.60 mm thickness.
- The spray-on coatings target drone, aircraft, and naval applications, with three variants covering X, Ku, S, C, and broadband frequency ranges.
Making a drone invisible to radar used to require years of classified engineering work, precision manufacturing, and a defense budget measured in billions. A Chinese company based in Shenzhen is now selling the core technology by the kilogram, available in standard packaging and applied with a spray gun. Star-Navi’s XRAM-C Series radar-absorbing coatings represent the commercial maturation of a capability that advanced militaries have guarded carefully for decades, now available to any drone manufacturer or operator willing to apply a coat of black-gray liquid to their airframe before a mission.
Radar-absorbing material works by converting incoming radar energy into heat rather than reflecting it back toward the detection system trying to locate the aircraft. A standard metal or composite surface reflects most incident radar energy back toward the transmitter, producing the strong return signal that allows a radar operator to identify, track, and engage a target. A properly applied radar-absorbing coating intercepts that energy before it reaches the reflective surface beneath, dissipating it as thermal energy instead. The result is a weaker return signal, a smaller apparent radar cross-section, and a target that is harder to detect, track, and engage at the ranges where radar-based air defense systems operate most effectively.
Star-Navi’s XRAM-C Series addresses that physics across three product variants optimized for different threat radar frequencies. The XRAM-C105 targets X and Ku band frequencies, which cover a wide range of fire control radars, airborne intercept radars, and the millimeter-wave sensors increasingly used in counter-drone systems. The XRAM-C112 addresses S and C band, covering surveillance radars and the medium-range search systems that air defense networks use to build their initial picture of the airspace. The XRAM-C113B provides broadband coverage across C and X band combined, trading peak performance at any single frequency for consistent absorption across the widest range of potential threat radars. The availability of three distinct formulations reflects a sophisticated understanding of the operational environment: different threat radars operate at different frequencies, and a coating optimized for one band may perform poorly against another.
The technical specifications Star-Navi publishes are detailed enough to evaluate the coating’s claimed performance against known radar physics. The company claims average radar reflection loss of at least 3.0 dB across 8 to 12 GHz and at least 3.5 dB across 2 to 6 GHz, at coating thicknesses ranging from 0.40mm (0.016 in) to 0.60mm (0.024 in). A 3 dB reduction corresponds to halving the reflected radar power reaching the receiver, which meaningfully degrades the signal-to-noise ratio that detection algorithms rely on to distinguish a target from background clutter. Surface density stays at or below 1.1 kg per square meter (0.23 lb per square foot) at the thinner specification, which matters for drone applications where every gram of added weight reduces range, payload capacity, or endurance. Adhesion strength of at least 10 megapascals ensures the coating remains bonded to the airframe through the thermal cycling and mechanical vibration that flight imposes, and the company’s stated heat resistance of 250 degrees Celsius (482°F) for 100 hours without degradation addresses the elevated temperatures that high-speed airframes or engine-adjacent surfaces can experience.
The salt spray resistance specification, 2,000 hours without blistering, rusting, or cracking, is a standard accelerated corrosion test used across the aerospace and naval industries to evaluate coating durability. Meeting that threshold positions the XRAM-C Series for naval applications where salt-laden air is a constant environmental challenge, in addition to the land and air platforms that represent the coating’s primary drone market. The customizable formulation option that Star-Navi offers allows customers to specify performance requirements for particular frequency bands or environmental conditions outside the standard product parameters, which is the kind of flexibility that defense procurement programs require when the operational scenario differs from the baseline testing conditions.
The application method, spray coating onto prepared surfaces followed by curing, requires no specialized manufacturing infrastructure that a drone producer or military unit would not already possess. This accessibility is precisely what separates commercial radar-absorbing coating products from the classified treatments applied to advanced stealth aircraft, which require controlled manufacturing environments, specialized tooling, and depot-level maintenance facilities to apply and repair. Star-Navi’s packaging in 1 kg (2.2 lb), 5 kg (11 lb), and 10 kg (22 lb) containers further emphasizes the product’s accessibility: this is material sold by weight, applicable at the unit level, not a factory process requiring capital investment.
Star-Navi is not alone in pursuing this market. Turkey has also produced a researcher working in the same space: Yunus İnce has been developing a spray-on radar-absorbing material called Kürşat 3.0, which The Defence Blog reported on previously, with İnce claiming an attenuation figure of 43.2 dB in his testing using volcanic basalt and pumice structures. That figure would represent performance in a class with classified military stealth treatments rather than commercial coating products. What both the Turkish and Chinese developments share is the same fundamental insight: radar signature reduction does not have to be a manufacturing process embedded in the original platform design. It can be a coating applied after the fact, to existing hardware, by operators in the field.
The proliferation of affordable radar-absorbing coating technology carries consequences that extend beyond any individual product or company. Counter-drone radar systems are being deployed more widely across both military and civilian security applications as the drone threat has expanded, and the operators of those detection systems have been able to count on most drones presenting detectable radar cross-sections because radar stealth has been technically and economically out of reach for most drone manufacturers. As commercial radar-absorbing coatings become readily available and demonstrably effective at meaningful frequency ranges, that assumption erodes. A drone coated with a material that halves its radar return signature is detectably harder to track than an uncoated drone, and a coating that delivers several more decibels of attenuation than that becomes genuinely difficult to handle for systems not designed to cope with reduced cross-section targets.