Lumenok BR 425 Replacement Battery (2-Pack) The Lumenok RBS is a 2 pack of ( BR-425) replacement batteries for Lumenok Crossbow bolt ends.. Lumenok replacement batteries can be used to repower your Lumenok Crossbow nocks. They can also be used in the following Lumenok models to reduce the overall weight by 4 grains: the Lumenok Signature, the Lumenok the Lumenok H. For use in crossbow Lumenoks Easy to install 2 batteries per pack