There are several open ended dual parabolic adjustable reflectors available, but none come close to the Powerplant Mantis reflector for its versatility and strength.
The Powerplant Mantis reflector is an adjustable dual parabolic, super alloy reflector that delivers an even spread of light to your garden below and the simple design of the Mantis allows free air flow around the lamp, minimising the heat building up below.
The Mantis can be adjusted to wide settings and positioned incredibly close to your plants for maximum light transferral and area coverage. Alternatively, the wings may be adjusted to more narrow settings and the reflector positioned further away from your plants to suit the light and heat requirements of more sensitive plants or plant stages. The Mantis is so flexible, you can even have one wing in a narrow setting and one in a wide setting to encourage growth in unproductive areas of your grow room. The ceramic lamp holder and cable is also adjustable and it can be positioned to suit small lamps and large lamps so they are sat central in the reflector, to spread the light more evenly.