High resolution gamma scintillation detector with 25.4 x 25.4 mm Lanthanum Bromide (LaBr3) crystal. Lanthanum Bromide crystals provide excellent resolution typically 3.5% or better at 662 keV. 

The LaBr3 crystal is encapsulated and axially mounted to a 1.5" (38 mm) ADIT PMT with 12 M Ohm divider and a single SHV connector (BNC available on request), the whole assembly is padded and enclosed in an anodised aluminium housing with wall thickness ~0.6 mm.