The board of directors of Astral Poly Technik on Friday approved a proposal to issue bonus shares in the proportion of 1: 4 (one bonus equity share for every four held), as on the record date, which would be announced later. The decision is subject to approval of the shareholders of the company, it further said. Shares of Astral Poly Technik edged down 1.16 per cent at ₹1,219.20 on the BSE.