I've looked high and low for 904 nm LED's with fast (< 20nsec) rise-times and decent intensity but haven't found any. Panasonic makes one at 905nm but the rise time is 700nsec! The closest I've found is 890nm from Vishay but I don't know how sharp the IR filters are on guns and detectors.
Does anyone know what make/model LED's manufacturers like Blinder use ??