Which of the following is the longest acting ocular beta blocker ?

Beta blockers used in Glaucoma- Timolol, levobunolol, Carteolol, betaxolol Metoprolol, though a beta blocker is not used for glaucoma because of its local anaesthetic property. Drugs having local anaesthetic property will increase the risk of corneal ulcers. Betaxolol is longer acting than Timolol or others.