Exo Terra T5 UVB Fixture 90cm 39W | PT4257 Vivarium Hood

The ET T5 UVB Fixture 90cm (PT4257) is a high-performance T5 fluorescent hood designed specifically for reptile terrariums. Built around a 90cm, 39W tube, it is engineered to work with T5 VHO UVB bulbs and is compatible with any standard T5 linear fluorescent tube of the correct wattage and length. If you are running a larger vivarium and need reliable, flicker-free UVB output, this fixture is built for the job.

Electronic Ballast & Lamp Performance

The high-quality electronic ballast eliminates flickering entirely, which matters both for your animals and for the longevity of the bulb itself. It also offers built-in protection against over-voltage, over-current, overheating, and end-of-lamp-life (EOL) events, and comes with a grounded plug as standard for maximum electrical safety.

Polished Reflector

The internal reflector is highly polished and increases usable lamp output by up to 2.5 times compared to an unshielded bulb. This makes a meaningful difference to the UVB intensity reaching your animals on the floor or branches of the enclosure, particularly in deeper or taller terrariums.

Placement & Installation

The fixture can be placed directly on top of terrarium mesh for straightforward setups, or mounted inside the enclosure using compatible installation accessories sold separately. For extra-long enclosures, multiple units can be positioned side by side using optional mounting hardware.

Linking Multiple Fixtures

• Up to 10 fixtures can be linked together using optional grounded interconnection cables
• Interconnection cables are sold separately and available in 30cm or 60cm lengths
• Linking allows all connected fixtures to be controlled via a single timer, reducing cable clutter significantly

Important: Pairing UVB with Basking Heat

UVB alone is not sufficient — it should always be paired with a strong source of infrared-A (near-infrared) radiation, such as a dedicated halogen or intense basking spot bulb. This combination more closely replicates the full solar spectrum that basking reptiles require for thermoregulation and vitamin D3 synthesis.

Available in four lengths and wattages to suit enclosures of different sizes, the 90cm 39W variant is a well-specified choice for medium to large terrariums where consistent, high-output UVB coverage is a priority.