I can only agree with BN, having had Pards and a couple of other similar units, I have never been able to part with my NiteSite Viper and Wolf units, old hat, may be but they work and have accounted for thousands of rats and hundreds of rabbits so despite them being out of production you do get them on ebay from time to time. My shooting partner makes his version when required for about £100 but That one shown above the NVS30 looks spot on.
Phil