Based in Petaluma, California, H3R Aviation offers fire extinguishers and mounting options for fixed- and rotary-wing aircraft of all types and sizes. Its recently introduced Halotron BrX fire extinguishers incorporate halon-alternative agents that match the halon industry standard requirements.

Ranging in size from a 1.92-lb. 2B:C-rated (B flammable/C electrical) extinguisher for smaller aircraft, to a 12.5-lb., 2A:10B:C rated (2.5 gal., 102, B:C) extinguisher for cargo areas on larger aircraft, Halotron BrX extinguishers are designed to balance effectiveness and sustainability, with a low global warming and ozone depletion potential. 

With a service life of 12 years and minimal maintenance requirements, all of the extinguishers meet UL, ISO and European standards and are an FAA-compliant Halon 1211 alternative.
https://marketplace.aviationweek.com/company/h3r-aviation-inc

All Aircraft Fire Suppression
 

The Collins Aerospace avionics business unit includes fire protection systems for most aircraft from large commercial to light business jets and military platforms as well as ground vehicles.

With its fire-protection system headquarters in Wilson, North Carolina, along with global supporting sites, Collins supplies Kidde fire protection products, ranging from cabin mounted handheld extinguishers to engine, APU and cargo bay bottles.

The Collins 2-BTP Handheld Fire Extinguisher is an environmentally friendly, EPA Significant New Alternatives Policy (SNAP)-approved cabin extinguisher that uses a “green” non-ozone depleting agent in place of Halon 1211. 

Collins’ Lavatory Waste Bin Extinguisher meets international requirements for removal of ozone-depleting Halon 1301 from commercial aircraft.  These non-Halon fire suppression products are crafted for decades of high reliability, low-maintenance service.
https://marketplace.aviationweek.com/company/collins-aerospace

Self-Activating Fire Suppression

Firetrace International of Scottsdale, Arizona, manufacturers fire suppression products that are self-activating, with no human intervention required. The manufacturer’s products, marketed under the Firetrace International brand, are targeted specifically for aircraft ground support equipment.

As a standalone product, the Firetrace system does not require an outside electrical connection to activate, allowing for 24/7 protection of ground service equipment, no matter where it is being operated or parked. This is accomplished with a proprietary pressurized polymer fire detection tubing as the fire detector.  

Upon detecting fire, the tubing will rupture within 5-10 sec., activating a pneumatic valve and releasing the fire suppression agent through a series of discharge hoses and nozzles.
https://marketplace.aviationweek.com/company/firetrace-international