A release mechanism for separating sections of a mooring line assembly, comprising: a main body comprising first and second mating sections (20, 30) disconnectable along a line of disconnection, the end of each section having openings to which sections of said mooring line can be attached, each of said first and second sections (20, 30) having a transverse inwardly extending flange (22, 32) adjacent the line of disconnection; one or more movable locking shoes having a locking portion bridging said flanges(22, 32) and line of disconnection, said locking shoes having opposed surfaces for engaging said flanges (22, 32), said shoes locking said first and second sections (20, 30) together when said opposed surfaces thereof are maintained in contact with said flanges (22, 32); each of said shoes having an inwardly curved rocker portion at one end thereof adapted to contact the side walls when moved radially outwardly, the outward movement of said rocker portion causing the locking portion to move radially inwardly and disengage the opposed surfaces of said locking portion from said flanges (22, 32) to thereby permit disconnection of said body sections (20, 30); a button comprising an exterior cam surface located adjacent said locking shoes and in a first position holding said locking portion of said locking shoes in contact with said flanges (22, 32), said cam surface being adapted to contact and move said rocker portion radially outwardly and cause said locking portion of said locking shoes to move away from said flanges (22, 32) and thereby permit separation of said sections (20, 30), when said cam surface is in a second position; a remotely operable acoustic internal assembly for moving said button between said first and said second positions, said internal assembly connected to said button by a shaft; and a mechanical means for moving said button from said first position to said second position, wherein said locking shoes can move to a second unlocked position and said first and second sections (20, 30) of said release mechanism can disconnect, said mechanical means operable by application of an external force to said mechanical means. a main body comprising first and second mating sections (20, 30) disconnectable along a line of disconnection, the end of each section having openings to which sections of said mooring line can be attached, each of said first and second sections (20, 30) having a transverse inwardly extending flange (22, 32) adjacent the line of disconnection; one or more movable locking shoes having a locking portion bridging said flanges(22, 32) and line of disconnection, said locking shoes having opposed surfaces for engaging said flanges (22, 32), said shoes locking said first and second sections (20, 30) together when said opposed surfaces thereof are maintained in contact with said flanges (22, 32); each of said shoes having an inwardly curved rocker portion at one end thereof adapted to contact the side walls when moved radially outwardly, the outward movement of said rocker portion causing the locking portion to move radially inwardly and disengage the opposed surfaces of said locking portion from said flanges (22, 32) to thereby permit disconnection of said body sections (20, 30); a button comprising an exterior cam surface located adjacent said locking shoes and in a first position holding said locking portion of said locking shoes in contact with said flanges (22, 32), said cam surface being adapted to contact and move said rocker portion radially outwardly and cause said locking portion of said locking shoes to move away from said flanges (22, 32) and thereby permit separation of said sections (20, 30), when said cam surface is in a second position; a remotely operable acoustic internal assembly for moving said button between said first and said second positions, said internal assembly connected to said button by a shaft; and a mechanical means for moving said button from said first position to said second position, wherein said locking shoes can move to a second unlocked position and said first and second sections (20, 30) of said release mechanism can disconnect, said mechanical means operable by application of an external force to said mechanical means.