Max 72 dB FCC GainUp to 5,500 Sq FtVerizon / AT&T / T-Mobile5G & 4G LTE Multi-Band
Stop walking out to the driveway just to finish a phone call. The FCC-certified Cosari SignalMax 5G Pro captures weak distant cell tower signals with a high-gain directional Yagi antenna, amplifies them up to 32× (+72 dB), and broadcasts crystal-clear 5G & 4G LTE across up to 5,500 sq ft.
$219.99 $439.99 SAVE 50% $184.99 each when you buy 2
Metal siding, Low-E window glass, concrete walls, and dense pine trees block up to 95% of cell radio waves before they reach your couch. Our weatherproof outdoor Yagi directional antenna bypasses your walls entirely, locking onto distant towers and amplifying signal strength by up to 32×.
Blindly guessing which direction to point an outdoor antenna is a nightmare on LED-only boosters. SignalMax 5G Pro features a live color LCD readout showing real-time decibel (dBm) gain for Bands 2, 4, 5, 12/17, and 13—plus Automatic Gain Control (AGC) that prevents oscillation automatically.
Whether your family uses Verizon, your guests use AT&T, or your work hotspot runs on T-Mobile, the indoor directional panel antenna broadcasts 5G and 4G LTE across 5,500 sq ft for unlimited simultaneous users—plus includes a flat window entry cable so you don’t even have to drill through walls.
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Eliminate Dropped Calls, Failed Texts & Slow 5G Data in Every Room
$219.99$439.99SAVE 50%
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✓ End Dead Zones Inside Metal-Roof Homes & Cabins: standing-seam metal roofs, stucco wire mesh, and basement concrete act like a Faraday cage against cell towers. SignalMax 5G Pro pipes strong outdoor tower signal straight into your living room.
✓ Faster 5G & 4G Data + Extended Phone Battery: when your phone hunts for a 1-bar signal, its internal transmitter runs at maximum power and drains your battery by noon. Boosting your indoor bars to 4–5 bars speeds up data up to 10× and adds hours of daily battery life.
✓ No-Drill Window Entry Included: don’t want to drill a hole through your exterior wall? Use the included ultra-flat window ribbon jumper to close your window sash right over the cable.
✓ FCC Certified & Carrier Approved: features Automatic Gain Control (AGC) and Anti-Oscillation Shutdown that meet all FCC Part 20 standards.
Cosari SignalMax 5G Pro 5-band LCD amplifier unit, outdoor directional Yagi antenna with mounting bracket, indoor wall panel antenna, 50-ft low-loss coax cable, 16-ft coax cable, flat no-drill window pass-through cable, AC power supply, step-by-step installation guide.
Free US shipping. Orders ship within 1–2 business days with full tracking. Return within 30 days of delivery for a full refund under our 100% money-back guarantee. Faulty, damaged or wrong item: we email a prepaid return label and you choose a refund or replacement. See our refund policy.
Not all cell phone signal boosters are equal. Cosari SignalMax 5G Pro leads on 72 dB gain, live LCD diagnostics, and coverage area — and is certified Best Choice of 2026.
| Feature | Cosari SignalMax 5G Pro★★★★★ | Others★★☆☆☆ |
|---|---|---|
| Max System Gain | 72 dB (FCC Max) | 60–65 dB |
| Indoor Coverage Area | Up to 5,500 Sq Ft | 1,500–2,000 Sq Ft |
| Live 5-Band LCD Screen | Real-Time dB Readout | Blinking LED Only |
| All Carriers (VZW/AT&T/TMO) | ✓ | ✕ |
| No-Drill Flat Window Cable | ✓ | ✕ |
| 66 Ft Low-Loss Coax Included | ✓ | ✕ |
| Award Winner 2026 | ✓ | ✕ |
Turns a barely usable 1-bar outdoor signal (-105 dBm) into 4–5 solid bars indoors.
Routes cell signal past steel roofs, foil insulation, and concrete walls across 5,500 sq ft.
Verizon, AT&T, T-Mobile, and US Cellular phones all get boosted simultaneously.
Shows exact gain numbers on every frequency band so aiming the Yagi antenna takes 5 minutes.
Works 100% off-grid without broadband WiFi and never charges a monthly subscription.
Includes a paper-thin window pass-through jumper so you don’t have to drill through siding.
Attach the weatherproof Yagi antenna to your roof pole, eave, or deck rail where you get at least 1 bar.
Use the flat no-drill window ribbon and 50-ft coax to connect the outdoor antenna to the indoor LCD booster.
Set the indoor panel antenna 20+ feet away facing your living space and watch your phones jump to 5 bars.
Yes—as long as your phone can pick up at least 1 weak bar outside on your roof, deck, or yard. The outdoor Yagi antenna captures that faint outside signal and amplifies it up to 32× inside your home.
Yes! Because SignalMax 5G Pro amplifies all 5 primary North American cellular bands (Bands 2, 4, 5, 12/17, and 13) simultaneously, it works with every US and Canadian carrier and prepaid MVNO at the same time.
No. Unlike carrier femtocells that require high-speed broadband internet, SignalMax 5G Pro communicates directly with cellular towers through the air—making it ideal for rural homes and off-grid cabins.
Simply rotate the outdoor antenna in 45-degree increments while watching the live decibel (dB) bar graphs on the SignalMax LCD screen—lock it down where the numbers peak.
No! We include a paper-thin flat window pass-through jumper cable that lets you route the coax right under a closed window sash without drilling.
Yes. SignalMax 5G Pro is 100% FCC Part 20 certified with built-in Automatic Gain Control (AGC) and oscillation protection, pre-approved for use on Verizon, AT&T, and T-Mobile.
Test it on your property for 30 days. If it doesn’t dramatically improve your indoor signal and data speeds, return it for a full 100% refund.
Garrett & Denise W.
★★★★★Went from 0 bars under our new metal roof to 5 full bars!
The day we put a standing-seam metal roof on our farmhouse in Tennessee, our Verizon phones died completely inside. We had to stand on the porch in the rain to take calls. Mounted the SignalMax Yagi on our old satellite dish bracket on the eaves—now we have 4 to 5 bars in every bedroom and kitchen.
Owned 5 weeks · Tennessee · verified buyer
clint R.
★★★★★Download speeds jumped from 1.2 Mbps to 44 Mbps
Tested with Speedtest before and after in my basement office. Night and day difference.
Owned 3 weeks · Montana
Bruce H.
★★★★★The LCD screen makes aiming the Yagi 10× easier than weBoost
I helped my neighbor install a $550 weBoost Home MultiRoom last year and it only had a tiny green/red blinky light. Having actual dB numbers for all 5 bands on the Cosari LCD screen let me aim straight at the Band 13 Verizon tower in 5 minutes.
Owned 6 weeks · Idaho
Karen & Jim L.
★★★★★Boosted both my AT&T iPhone and my husband’s T-Mobile work phone
At our lake cabin in northern Wisconsin, both AT&T and T-Mobile used to drop every 2 minutes. This one unit boosted both carriers at the same time so we can finally work remotely from the lake on Fridays.
Owned 1 month · Wisconsin
Wade M.
★★★★★Flat window ribbon meant zero holes drilled in our log cabin
Slid the flat coax right under the guest bedroom window sash and locked the window shut.
Owned 2 weeks · Maine
duane K.
★★★★★Bought the 2-pack—one for the house, one for my 40×60 steel pole barn
Inside a steel shop building your phone is a paperweight. Installed the second kit in my pole barn and now I can stream music and take customer calls under the lift.
Owned 6 weeks · Ohio · bought 2
Patricia S.
★★★★★My phone battery doesn’t die by 2:00 p.m. anymore
I didn’t realize how much battery my iPhone burned searching for 1 bar all day. Now that I have 5 bars inside, my phone finishes the day at 60%.
Owned 4 weeks · Virginia
lester P.
★★★★★Keep 20+ feet of separation between the outdoor and indoor antennas
Follow the manual on vertical/horizontal separation so the AGC gives you the full 72 dB gain. Works awesome once placed right.
Owned 3 weeks · Missouri
Trevor G.
★★★★★Saved my T-Mobile 5G Home Internet gateway!
Placed the indoor panel antenna 8 feet from my T-Mobile gateway in our rural house and our home internet speed tripled.
Owned 5 weeks · Texas
norma B.
★★★★★Peace of mind for my 82-year-old parents in the mountains
Installed this at my parents’ house in West Virginia where landlines go out in storms. Now they have reliable 911 and family cell coverage.
Owned 1 month · West Virginia
Hank C.
★★★★★Thick, shielded 50-foot coax cable included
Not the skinny RG-59 wire—real low-loss shielded coax with weatherproof boots.
Owned 4 weeks · Colorado
Melanie D.
★★★★★Finished our basement and this brought full signal downstairs
Mounted the indoor panel at the top of the basement stairs and the whole 1,800 sq ft lower level has 5 bars.
Owned 5 weeks · Minnesota
royce T.
★★★★★Runs cool and completely silent
Cast aluminum fins keep it barely warm to the touch 24/7.
Owned 3 weeks · Arizona
Glen F.
★★★★★Even works with our cellular trail cameras near the barn
Pictures upload in seconds now.
Owned 4 weeks · Kentucky
Cathy J.
★★★★★Arrived in 2 days with clear illustrated instructions
Had the whole system running in 35 minutes on Saturday morning.
Owned 2 weeks · Georgia
marshall V.
★★★★★Half the price of SureCall or weBoost and works better
72 dB gain is no joke. Best investment we’ve made for our country property.
Owned 2 months · Oregon