Air Products (NYSE:APD) over the weekend boosted its hostile takeover bid of rival Airgas (NYSE:ARG) to $5.5 billion.

Airgas said it is reviewing the revised $65.50-a-share offer, which is all-cash and represents a 50% premium on shares of Airgas as of Feb. 4, the day prior to the initial acquisition bid.

Air Products said it expects the proposed acquisition would “immediately” boost the company’s earnings per share on both a GAAP and cash basis, excluding one-time costs.

John McGlade, CEO of Air Products, said the 50% premium should remove “all risks and future uncertainties” for Airgas shareholders, who he urged to elect its nominees to the board and approve its by-law proposals.

“All principal closing conditions have been satisfied.  After more than 10 months of delay, there is no reason for the Airgas Board to refuse to negotiate a deal with us now.  We look forward to the vote of Airgas shareholders and are confident they will make the right choice,” McGlade said in the statement.

Unless extended, Air Products said the revised offer will expire at midnight on October 29.

Airgas advised its shareholders to “take no action at this time” while it reviews the new offer to “determine the course of action that it believes is in the best interest of the company and its stockholders.”