This is a brand new replacement lamp module manufactured to exactly the same specifications as the projector manufacturers original. A Diamond lamp uses the manufacturer"s original bulb and fits it inside a high quality Diamond Lamp housing guaranteeing that the lamp not only delivers and on price but also on quality, to the same standard as the manufacturer"s original. Diamond Lamps are so confident in their product that they even offer an extended 120 day warranty. This lamp is 100% compatible with the following VIEWSONIC projector model PJ1158. Matching Part Number(s) RLC-021 .