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GrowPros Solutions - HM660 660 Watt 4ft by 4ft LED Grow Light - Green Thumb Depot
GrowPros Solutions HM660 660 Watt 4ft by 4ft LED Grow Light

GrowPros Solutions HM660 660 Watt 4ft by 4ft LED Grow Light

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SKU: GPS-HM-660

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$499.95
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The GrowPros Solutions HM660 LED Grow Light is a high-performance horticultural lighting system engineered for indoor cultivation, hydroponic grow rooms, and greenhouse environments. Designed to deliver powerful illumination across a 4 ft × 4 ft canopy, this 660-watt full-spectrum LED fixture provides balanced light output that supports plant development from the vegetative stage through flowering.

Built with a sun-like full spectrum enhanced with deep-red LEDs, the HM660 replicates natural sunlight to maximize photosynthesis and encourage vigorous plant growth. This optimized spectrum helps improve plant structure during the vegetative stage and boosts flowering performance for higher crop yields and improved quality.

The fixture produces approximately 1716 µmol/s of PPF at 660W and up to 1820 µmol/s when boosted to 720W, delivering strong canopy penetration and consistent PPFD across the grow area. With a photon efficacy of about 2.6 µmol/J, the HM660 provides powerful output while maintaining energy efficiency compared with traditional HID or HPS lighting systems.

Designed for commercial cultivation environments, the HM660 features an integrated dimmer adjustable from 0–100% with a 110% boost mode, allowing growers to fine-tune light intensity according to plant growth stages. The system also supports 0–10V dimming and controller integration, including compatibility with professional control systems such as TrolMaster Hydro-X for automated lighting management.

The fixture incorporates a foldable multi-bar design with passive cooling, ensuring efficient heat management and quiet operation. Its modular structure includes extendable side bars that can be added to expand coverage for larger grow trays such as 3 ft × 6 ft or 4 ft × 6 ft setups. Built with durable components and an estimated lifespan exceeding 54,000 hours, the HM660 offers long-term reliability for professional growers.

Key Features

  • 660W full-spectrum LED grow light optimized for indoor cultivation

  • Coverage area: ideal for 4 ft × 4 ft grow spaces (up to 5 ft × 5 ft)

  • High output: up to 1820 µmol/s PPF at 720W boost mode

  • Photon efficiency: approximately 2.6 µmol/J PPE

  • Full spectrum with deep-red LEDs for both vegetative and flowering stages

  • Integrated dimmer with 110% boost capability

  • 0–10V dimming and controller compatibility (TrolMaster Hydro-X supported)

  • Foldable multi-bar design for easier installation and maintenance

  • Passive cooling system for low heat and quiet operation

  • Energy-efficient LED technology offering up to 30% savings vs HID/HPS lighting

  • Built for commercial indoor farms, grow tents, hydroponics, and greenhouse cultivation

Is the HM660 a Reliable Option?

The GrowPros HM660 LED Grow Light is designed for efficient cultivation, providing full-spectrum lighting with deep red support for all plant growth stages. With 660W output, it delivers strong PPFD performance, balanced 4ft by 4ft canopy coverage, and energy-efficient operation. Built with durable construction and stable thermal management, it ensures dependable performance, making it suitable for growers seeking consistent yields in both indoor and commercial growing environments.

Features & Benefits

Specifications

What is included?

Warranty & Returns

Features

High-Performance LED Growing Efficiency Output

Built for serious growers, the GrowPros HM660 LED Grow Light delivers full-spectrum lighting with deep red support for enhanced plant development. With powerful 660W output, it provides strong light penetration, balanced 4ft by 4ft canopy coverage, and efficient operation. Designed for durability and consistent performance, it promotes healthy growth, improved flowering, and reliable yields in both commercial cultivation setups and advanced indoor growing environments.

High LED Density

Wide Coverage Area

Full Spectrum Lighting

High PAR Output

Controller Compatibility

Passive Cooling System

Benefits of LED Grow Lights

LED grow lights offer numerous benefits for plant cultivation. They are energy-efficient, customizable in spectrum, emit minimal heat, and have a long lifespan. These qualities reduce costs, enhance growth, and promote environmentally friendly and low-maintenance cultivation practices.

Instant On/Off

It allows precise control over light cycles.

Full Spectrum Lighting

This promotes healthier and more robust plant growth.

Low Heat Emission

This reduces the risk of heat stress and saves them from damaging

Easy Installation

LED grow lights require less maintenance, saving you time and effort.

Optimized Light Output

Allows you to adjust the light spectrum to suit different plant types and growth stages

Power Saver

LED grow lights save energy, costs, and promote sustainable cultivation.

Durable Design

Constructed with top-quality materials, ensuring prolonged use in various conditions.

Consistent Output

Engineered for sustained performance, guaranteeing optimal light output over time.

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Why GrowPros Solutions?

GrowPros Solutions stands out for delivering high-performance cultivation equipment designed by experienced growers. With over 25 years of industry knowledge, the company focuses on innovation, efficiency, and affordability, helping growers maximize yields and plant quality. Their in-house manufacturing enables faster product development and reliable performance. By offering advanced lighting technologies and practical solutions, GrowPros supports both commercial and small-scale cultivators in achieving consistent, high-quality results.

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Spectrum Matters

The GrowPros HM660 LED Grow Light delivers full-spectrum lighting with deep red in a high-performance design to support plants from vegetative growth through flowering. Its multi-bar layout ensures even light distribution across 4ft by 4ft grow areas, improving photosynthesis and canopy development. With energy-efficient operation and optimized spectrum output, it promotes strong growth, enhanced flowering, and consistent yields for both commercial cultivation setups and indoor growing environments.

Balanced Spectrum Output

Designed for vegetative and flowering stages with full-spectrum lighting and deep red for optimal plant development.

Uniform 4x4 Coverage

Multi-bar LED structure provides even light distribution, reducing hotspots and improving canopy consistency.

Efficient Power Performance

660W system delivers strong intensity with energy-efficient output for dependable growing results.

Customer Reviews


Trusted by authentic customer reviews from verified buyers worldwide.
If I could rate 6 stars I would!
If I could rate 6 stars I would! My representative Edouard B. has been shockingly responsive! Like - oh my god - an actual SERVICE oriented company. He's dug into my odd connectivity issues I've been having - and following up in an AMAZINGLY timey manner. No shit. You'll be impressed! (And the price was also unbeatable, quick shipping...it's all PERFECT). Thank you Ed!!
Jim D
Customer service was outstanding great…
Customer service was outstanding great people to deal with they understand your needs and they will do their best to fulfill them there is no way I can complain about them because they are the best help out there.Thanks green thumb depot. I’ll definitely order from them again
Glenn Appleton
The machine is doing just what my…
The machine is doing just what my salesman told it would do (I appreciate you Ed thank you) . The machine is what we need for our new business we’re starting up, soon to be llc and licensed. We are getting a lot of clients wanting our services. Ed I will be needing more of your products, thank you again.
Freddie
Fantastic
Great prices, fantastic customer service, and mind blowing shipping! Incredible. Will be using again and telling anyone in need.
Kar
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FAQ Section

What is the wattage of the HM660?
The HM660 operates at 660W with the ability to boost up to around 720W, providing flexible intensity for different growth stages and higher output when needed.
What type of spectrum does it use?
It delivers a full-spectrum light enhanced with deep red wavelengths, closely mimicking natural sunlight to support strong vegetative growth and improved flowering performance.
Can it be used for all growth stages?
Yes, the HM660 is designed for full-cycle growing, making it suitable for seedlings, vegetative stages, and flowering without needing additional lighting systems.
Is the HM660 energy efficient?
The fixture is highly energy efficient, offering up to 30% savings compared to traditional HID and HPS lighting while still delivering powerful light output and performance.
Does it include dimming control?
Yes, it features an integrated dimmer that allows you to adjust light output from 25% up to 110%, helping you fine-tune intensity based on plant growth needs.
Can it connect to controllers?
The HM660 is compatible with major grow light controllers like TrolMaster, allowing automated control of light intensity, schedules, and integration into advanced grow systems.

Specifications

SPECS & DIMENSIONS

Dimensions 46.85 x 43.8 x 2.6 inches

STRUCTURE & LIGHT CONFIGURATION

Input Voltage Range

  • Supports 120–277V input, ensuring consistent and reliable performance across indoor and greenhouse grow environments.

LED Bar Arrangement

  • Multi-bar full-spectrum layout with deep red provides strong output and uniform canopy light distribution.

Driver System Integration

  • Built-in high-quality driver ensures efficient power delivery and long-lasting operational reliability.

Fixture Capabilities

Light Output Control

  • Integrated dimming system allows accurate intensity adjustment for optimized growth at every stage.
Brand GrowPros Solutions
RECOMMENDED SET-UP
Flower 4’X4′ AREA, MAX:5’X5′ AREA
Veg 4’X4′ AREA, MAX: 6’X6′ AREA
GENERAL DATA
Wattage 660W (Boost up to 720W)
Input Voltage 120V-277V
Control 0-10V dimming (0-100%), Wireless
Power Factor 0.9
Frequency 50/60Hz
Thermal Management Passive
Working Temperature -40ºF ~ 122ºF
THD 20%
PPF 1820 µmol/
PPFD 1325 µmol/(m2*s)
PPE 2.7 µmol/J
AC Voltage 120V / 208V / 240V / 277V
AC Current 5.96A / 3.50A / 2.95A / 2.71A
AC Power 713W / 700W / 695W / 685W
Power Factor 0.998 / 0.983 / 0.975 / 0.945
SpecSheet PDF

What is Included?

What’s in the box.

  • 1 x LED Grow Light
  • 1 x User Manual for Installation

Warranty Policy

It's recommended to contact GrowPros Solutions for specific warranty information related to their LED grow lights. Please note that warranty details may vary depending on the product model, purchase location, and other factors.

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