Hot Spot Concentrating Dish

Design specification includes the dish, a high-quality reflective film, hand pump vacuum (for evacuating the cavity formed between the reflective film and dish), a tripod with one telescoping leg (for elevation adjustment).

Physical specifications:
Mirror Diameter: 114 cm (45 in)
Reflective Surface: Aluminized Mylar Film
Reflective Area: 0,33 m³ (11.5 cubic ft.)
Weight: from 3.6 kg (8 lbs) to 4,5 kg (10 lbs);depending on configuration

A plastic lined cardboard film cover is provided to avoid punctures during handling, and also to prevent soiling of the reflective film.

The product comes along with instruction manual. View Frequently Asked Questions or contact the manufacturer.

This product has a 1-year warranty from date of shipment. With proper care, the product can last up to 10 years. The product is intended to be brought inside after use.  Most users hang them up on a wall. A Better Focus co. is currently testing a new film suitable for continuous use outdoors within an estimated lifecycle of 10 years. This new film is, however, more expensive. ^{Interview with manufacturer}

The dish has been successfully tested to -6.7 ºC (20 ºF).

Performance:
Point Focus Focal Length: Variable from 3 m (10 ft) to 6 m (20 ft)
Point Focus Minimum Focal Area: 10.16 cm (4 in)
Concentration: Equivalent of 130 suns
Time to Boil: 1.36 litres (48 oz.) of water in 15 minutes (at 900 W/m² sunlight intensity)
Vacuum Hold Time: Minimum of 2 hours- always cover dish when not in use
Maximum Heat Flux: 454 ºC (850 ºF)

Safety notes:  Always wear sunglasses when using the dish and do not stare at the hot spot for extended periods. Never leave the dish unattended to prevent accidental fires. Hot cooking surfaces can potentially burn. Replace cover or relieve the vacuum.

The dish cannot be stored outdoors. The product has one year warranty from date of shipment. Damage to the reflective film is not covered by the warranty.^{Interview with manufacturer}