I have 2 BRS carbon/GFO reactors up for sale - $20 each, buy them both and I will throw in a spare reactor cartridge. The cartridges are the newer model. These are in full working order except I took off the top piece (to mount them to a wall) and threw it away. If you plan on having them free standing in your stand like I did then this is not a issue. If you plan to mount these to a wall then I would pass on these. I am selling them because I picked up some phosban reactors which hold slightly more media then these do.
Pumps not included
Here is more info from Bulk Reef Supply:
The BRS GFO & Carbon Reactor features several distinct advantages over other brands.

Pumps not included
Here is more info from Bulk Reef Supply:
The BRS GFO & Carbon Reactor features several distinct advantages over other brands.
- Ultra-transparent media cartridge allows for clear viewing of reactor media
- Heavy duty plastic construction
- High quality easy to use double O-Ring push-connect fittings
- Easy to operate, clean and maintain
- Filter wrench included
- (2) 3 Ft. sections of tubing
- High quality ball valve for precise tuning
- Ability to run carbon and GFO at the same time
- Instantly attaches to popular pumps like Maxi-Jets using included push connect fittings
- 1/2" fittings and ports throughout reduce head pressure and provide ample flow rates
- Holds three cups of carbon (Approx. 300g) or two cups of GFO (Approx 290g)
- Dimensions: 14"H x 8.5"W x 5.5"
- Pump (optional) and media sold separately