The Lead Castle Type : LS 240 is designed to shield the G.M.Counters from background radiation with G.M. stand. The shield is of 40 mm thickness and is built up of FIVE interlocking middle rings. The top and bottom are covered by similar interlocking discs. A door is fitted in the bottom ring with 150 degree opening to facilitate easy access to the sample holding tray of G.M. Stand. The door is fitted with heavy duty hinges and the inner side of the lead shield is lined with thin aluminium sheet to minimize scattering.