Original price was: £35.00.£28.00Current price is: £28.00. inc VAT
The smallest Onyx decklight: a 20mm recessed marker giving low-level orientation light along paths, steps and terraces. 0.3W at 2700K, IP67 rated. Foot traffic only, this size is not driveable.
12V low-voltage system · 6-year warranty only when installed as a complete Lightpro system (Lightpro transformer, cable and connectors).
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12V Plug & Play System · 6-Year Warranty
12V low-voltage fitting: this light runs on the Lightpro 12V system and must be powered by a Lightpro 12V transformer via Lightpro cable and connectors. It cannot be wired directly to mains power. The Lightpro transformer plugs into a standard outdoor socket and steps mains power down to a safe 12 volts, so there’s no electrician needed and the cable doesn’t need to be buried.
Warranty – complete Lightpro system required: Lightpro’s 6-year manufacturer’s warranty only applies when this product is installed as part of a complete Lightpro 12V system, meaning Lightpro fittings, a Lightpro transformer, Lightpro cable and Lightpro connectors used together. Connecting it to another brand’s transformer, cable or connectors voids the warranty. It must be installed as the product manual describes, the included light source is excluded, and proof of purchase is required.
Make it a complete system with a Lightpro Power Pack
No Lightpro transformer and cable yet? Add a Lightpro 12V Power Pack (transformer, cable and connectors) and your lights qualify for the 6-year warranty as a complete Lightpro system.
With these lights about 1 m apart: Small (100 W, 25 m) runs up to 21, Medium (100 W, 50 m) up to 46, Large (150 W, 100 m) up to 92. Mixing lights? Go by your cable route and total watts – each Power Pack page explains how.
The Onyx 20 sets into a 20mm hole and all but disappears in daylight. After dark it gives a small point of warm 2700K light, enough to mark the edge of a step, the line of a path or the perimeter of a terrace without lighting the area itself. It is the subtlest fitting in the Onyx range and the one to use where a brighter marker would dominate.
Unlike the Onyx 30, 60 and 90, the Onyx 20 is not rated to be driven over, so specify it for pedestrian areas and keep the larger sizes for driveways and crossovers. Rated IP67 in a black plastic body with a 1 metre tail and F-connector. A matching mounting sleeve (237A) is available separately.

📄 Product sheet (PDF)📖 Instruction manual (PDF)▶ Installation video (YouTube)







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