Section 44(5)(b) in West Bengal Trade Unions Rules, 1998
(b)Every ballot box used at a polling station shall bear on the outside labels marked with(i)the serial number, if any, and the name of the particular election,(ii)the serial number and the name of the polling station,(iii)the serial number of the ballot boxes where more than one ballot box is used, and(iv)the date of the poll.