GEMEK 36ft SMA Male to SMA Female Coax Cable - Low Loss S-LMR400

In this review of the GEMEK 36ft SMA Male to SMA Female pure copper cable, the bottom line is simple: this is a purpose-built, low-loss extension for SMA-based cellular, WiFi and RF gear that needs a long, durable lead. The single biggest reason to buy is the S-LMR400 construction and all-copper connectors, which preserve signal over longer runs and higher frequencies better than thinner coax. It is most useful for installers and hobbyists who need a 36 ft (11 m) extension between SMA equipment and external antennas or repeaters, and who prioritize signal retention over a slim cable profile.

Key Features

• All-copper SMA connectors: Gold plated SMA male to SMA female connectors provide corrosion resistance and a stable 50 ohm connection for radios and routers.
• Low-loss S-LMR400 coax: The 10.3 mm diameter S-LMR400 core keeps signal loss lower across 36 ft, which helps maintain throughput for 3G/4G/5G and WiFi links.
• Double shielded construction: The braid and foil shielding reduce external interference and preserve signal quality in noisy RF environments.
• Wide compatibility: Works with SMA-equipped modems, routers, repeaters and radios from common networking and cellular vendors that use standard SMA connections.
• Durable build and strain relief: Heat shrink on both ends and a robust jacket allow 90 degree bends and a minimum bending radius of 2.44 in without damaging the core.

Who It's For

The GEMEK 36 ft SMA extension is aimed at technicians, ham radio operators, ADS-B and GPS enthusiasts, and anyone installing external antennas for cellular modems or WiFi boosters who needs a long, low-loss lead. It is especially well suited when signal retention over distance is more important than a thin, flexible cable.

Users who need a very flexible or very small-diameter cable for tight, concealed routing or TV coax fits should look elsewhere; some buyers report the cable and connectors feel stiff and the size may not match every device enclosure. Also note this is not an RP-SMA cable and is not intended for TV coax applications.

Pros & Cons

Pros

• Superior signal retention for 36 ft runs thanks to the larger S-LMR400 center conductor.
• Solid build quality with double shielding and gold plated all-copper SMA connectors.
• Wide 50 ohm compatibility with many modems, routers, repeaters and radio systems.
• Durable jacket and strain relief allow tight bends without immediate damage.

Cons

• Physically large and relatively stiff compared with thinner cables, making routing in tight spaces more difficult.
• Connector size and fit are not universal; some devices, particularly certain TV boxes or non-standard SMA fittings, may not mate cleanly.

Specifications

Connector 1	SMA Male plug (50 ohm)
Connector 2	SMA Female plug (50 ohm)
Length	36 ft (11 meters)
Coax type	Double shielded Low-loss S-LMR400 (10.3 mm / 0.4 in diameter)
Impedance	50 Ohm
Operating temperature	-20C to +70C
Minimum bending radius	2.44 in

Our Verdict

The GEMEK 36 ft S-LMR400 SMA extension is a solid value for anyone who needs a long, low-loss 50 ohm lead between SMA equipment and antennas. Its all-copper connectors, double shielding and larger center conductor translate to better signal retention over distance, making it a practical choice for cellular, WiFi and amateur radio installations where cable bulk is acceptable for improved performance.

Frequently Asked Questions

Is this an RP-SMA cable?
No, this is a standard SMA Male to SMA Female cable and is not an RP-SMA type.

Will it work with my cellular modem or WiFi booster?
Yes, it is compatible with SMA-equipped modems, routers and repeaters from common vendors that use standard SMA connectors, provided the device accepts the connector size.

Can the cable be bent tightly during installation?
The cable supports 90 degree bends in one inch or less and has a minimum bending radius of 2.44 in, but it is thicker and stiffer than smaller coax types so plan routing accordingly.