Helix Compose i3 Ci3 T20FM-AL MK2 Tweeters 0.75 Inch FlexMount Aluminum Dome
Couldn't Load Pickup availability
The HELIX Ci3 T20FM-AL MK2 is a pair of 0.75 inch (20 mm) aluminium dome tweeters from the COMPOSE i3 range, rated at 4 ohms with a frequency response of 2 kHz to 25 kHz.
This is the aluminium dome MK2 version, also supplied in the Ci3 K165.2FM-S3 MK2 and Ci3 K100.2FM-S3 MK2 component sets. A titanium dome version is available as the Ci3 T20FM-TI.
Key specifications
- Size: 0.75" / 20 mm
- Dome material: Aluminium
- Impedance: 4 ohms
- Frequency response: 2 kHz to 25 kHz
- Sensitivity: 91 dB @ 2.83 V / 1 m (88 dB @ 1 W / 1 m)
- Installation diameter: 28 mm
- Installation depth: 9.8 mm
- In the box: 2 tweeters, flush mounts, pods and mounting material
Developed Inside the Vehicle
COMPOSE is HELIX's answer to modern car design. Developed inside the vehicle, for the vehicle, it combines universal speakers with the advantages of vehicle-specific systems.
Matched to HELIX and MATCH Amplifiers
The COMPOSE i3 range uses smart 3-ohm technology on its midrange and midbass drivers to raise efficiency and maximum sound pressure. This tweeter is rated at 4 ohms. Impedances are matched to HELIX and MATCH amplifiers, so the pairing always delivers full performance. It pairs naturally with other COMPOSE i3 components such as the Ci3 K100.2FM-S3 4 inch FlexMount speakers.
FlexMount Fitting
The i3 series uses HELIX's FlexMount system, simplifying installation across a wide range of vehicles and factory speaker positions. Optional FlexMount20 adaptors allow fitment into existing factory tweeter locations.
Explore the full range in Helix Compose i3.
Specification
| Impedance | Z 4 Ω |
|---|---|
| Frequency response | 2,000 Hz - 25,000 Hz |
| Sensitivity | SPL 91 dB @ 2.83V / 1m |
| Voice coil | diameter Ø 20 mm |
| Cone | material Aluminum |
More specs
| |
What's Included
- 2 x Ci3 T20FM-AL MK2
- 2 x Tweeter flush mount
- 2 x Tweeter pod
- 2 x Mounting material
Helix
About the Helix CI21003
From our tech experts at CEN
The Helix Ci3 T20FM-AL MK2 is a pair of 0.75 inch (20 mm) aluminium dome tweeters from the Compose i3 range. They cover 2 to 25 kHz at 4 ohms with 91 dB sensitivity, need 9.8 mm of depth, and come with flush mounts and angled pods.
Who it suits
Owners of the Ci3 K165.2FM-S3 MK2 or Ci3 K100.2FM-S3 MK2 sets, where this is the supplied tweeter, and anyone building an i3 front stage. The titanium dome Ci3 T20FM-TI is the alternative used in other i3 kits.
Our tech experts advise
Use a high-pass from a DSP channel or a suitable crossover and never run them full range. Factory tweeter positions can often be used with an optional FlexMount20 adaptor, which keeps the install neat. Aim them at the listening position. Get in touch if you want help choosing.
Explore the full Helix range at CEN, with fast UK dispatch and expert advice from our Nottingham team. Shop all Helix
Recommended For You
Discover more top-rated gear, handpicked to go with what you're viewing
Have it Fitted By Our Team
Our team fits car audio, stereos, dash cams and vehicle security at our workshop in Beeston, Nottingham. Tell us your vehicle and we'll confirm the parts and a fitted price.
- 1
Tell us your vehicle
Make, model and year, and what you'd like fitted.
- 2
We confirm the parts
Fascia, wiring and interfaces checked for your car, with a fitted price.
- 3
Fitted at our workshop
Bring it to our Beeston workshop and we do the rest.
Unit 25 Technology Drive, Beeston, Nottingham NG9 1LA
More from Helix Compose i3
More options from the same range, in stock and ready to go
Helix Compose i3 Ci3 K100.2FM-S3 MK2 Component 4 Inch FlexMount Speakers 80w RMS
£259.99
View product
Helix Compose i3 Ci3 C100.2FM-S3 MK2 Coaxial 4 Inch FlexMount Speakers 80w RMS
£174.99
Helix Compose i3 Ci3 W130-S3 Midbass 5.25 Inch 13cm Speakers 90w RMS
£129.99
Helix Compose i3 Ci3 K165.2FM-S3 MK2 Component 6.5” FlexMount Speakers 100w RMS
£259.99
Helix Compose i3 Ci3 W165FM-S2 Woofers 6.5 Inch FlexMount Speakers 100w RMS
£129.99
Frequently Asked Questions
Q: Will these speakers fit my car?
A: Most car speakers are standard sizes, but mounting depth and fitting rings vary by vehicle. Check the size in the Specification tab against your vehicle, or contact CEN with your registration and we will confirm fitment and any adapters or fitting kits you need.
Q: Do I need an amplifier to run these speakers?
A: Not always. Most speakers will run from a standard head unit, but a dedicated amplifier lets them perform at their best, particularly for component sets and higher power handling models. The RMS figure in the Specification tab is the guide to how much clean power they can use.
Q: What is the difference between coaxial and component speakers?
A: Coaxial speakers combine the tweeter and woofer in one unit for a simple like-for-like upgrade. Component sets separate the tweeter and woofer with a crossover for better imaging and detail, and suit installs where sound quality is the priority.
Q: Do these come as a pair?
A: Unless stated otherwise, car speakers are sold in pairs. Check the product title and What's Included tab, which lists exactly what is in the box.
Q: Can CEN fit these speakers for me?
A: Yes. CEN offers professional installation from our Nottingham premises. Contact us to book an installation slot or ask for a fitting quote.
Q: What impedance are the Ci3 T20FM-AL MK2 tweeters?
A: They are 4 ohm tweeters with a 3.2 ohm DC resistance.
Q: How can the Ci3 T20FM-AL MK2 be mounted?
A: Flush mounts and angled tweeter pods are supplied, and they suit optional car-specific FlexMount20 adaptors for the original tweeter position.
Q: Do the Ci3 T20FM-AL MK2 tweeters need a crossover?
A: Yes, they should be run with a highpass crossover. In the HELIX Ci3 K100.2FM-S3 MK2 and K165.2FM-S3 MK2 sets they are paired with the Ci3 FX-UNI.2 crossover. An amplifier or DSP highpass filter can also be used.
Not Sure Where to Start?
Straightforward advice and the latest news from our Nottingham team.
All Guides and News →
Car Audio
Christmas Gift Guide 2026: Car Audio, Dash Cams and Outdoor Tech
Read the guide →
Car Audio
Upgrading Car Audio Without Replacing the Factory Stereo
Read the guide →
Car Audio
Amplifier Wiring Kits Explained: Gauge, Fuses and Earths
Read the guide →
Car Audio
New at CEN: Option Audio Drive-10Flat — Golf Mk8 Bass, Zero Boot Space Lost
Read more →
Car Audio
Car Speaker Sizes Explained: What Fits Your Car
Read the guide →
Car Audio
Alpine iLX-F905D Halo9 Review: The Big-Screen Upgrade for Almost Any Car
Read more →