We built this caravan heater around a 400V, 2500W shortwave halogen lamp because when you’re working with tight spaces, you need heat that’s dense and focused. The 300mm tube keeps the footprint small, so it slips into standard mounts without elbowing your wiring or other components out of the way. Here’s the thing about the 400V rating: it keeps the current draw lower on the supply side. That means your wiring gauge and protection devices stay simpler and more manageable—especially in a mobile setup. At 2500W, the heater throws off a lot of heat from a compact body, so you get a fast warm-up and immediate response the moment the cabin starts to feel chilly. And the 300mm length? It’s a sweet spot. Long enough to support the filament steadily and spread the heat evenly. Short enough to drop right into the recessed spots you already have. The halogen element is shortwave, which means it runs the filament hotter while staying stable. The internal halogen cycle helps prevent blackening over time, so the output stays consistent. The quartz envelope handles the jolt of rapid on-off cycling without cracking under thermal stress. Plus, the reflector coating pushes infrared energy forward, where you need it, instead of letting it spill uselessly to the sides. Installation is straightforward too. The R7s connector is a simple bi-pin fit that speeds things up and cuts down on wiring mistakes. No custom leads. You wire it, you mount it, you’re running. In a caravan, space and reliability matter. This heater delivers concentrated infrared warmth that hits fast, and the R7s connection makes replacement and maintenance simple. Just keep one thing in mind: because it packs so much heat into a small space, you’ll want solid ventilation and a thermal switch sized properly to prevent overheating in tight cabinets.