A ground engaging tool system comprising: a ground engaging tool (40; 400) having ground engaging surfaces and an adapter receiving cavity (43; 430), the adapter receiving cavity (43; 430) having a lock cavity (41; 420); an adapter having a nose portion which is generally shaped to fit inside of the adapter receiving cavity (43; 430); a lock (20; 200) rotatably positioned in the lock cavity (41; 420) to rotate between an unlocked position and a locked position, the lock (20; 200) including a slot (21; 210), characterised in that the nose portion of the adapter includes a post (10;120); and the slot of the lock is adapted to receive the post (10;120); and wherein, when the ground engaging tool (40; 400) is slid onto the nose portion of the adapter such that the nose portion is inside of the adapter receiving cavity (43; 430), the post (10; 120) is adapted to be received in the slot (21; 210) such that rotation of the lock (20; 200) does not cause the post (10; 120) to rotate, and wherein, when the ground engaging tool (40; 400) is slid onto the nose portion of the adapter such that the nose portion is inside of the adapter receiving cavity (43; 430) and the post (10; 120) is received in the slot (21; 210), the lock (20; 200) in its locked position is adapted to prevent the post (10; 120) from sliding out of the slot (21; 210) and to prevent the ground engaging tool (40; 400) from sliding off of the adapter, and, when the lock (20; 200) is rotated to its unlocked position, the post (10; 120) is adapted to slide out of the slot (21; 210), and the ground engaging tool (40; 400) and the lock (20; 200) are free to slide off of the nose portion of the adapter while the lock (20; 200) remains positioned within the lock cavity (41; 420). a ground engaging tool (40; 400) having ground engaging surfaces and an adapter receiving cavity (43; 430), the adapter receiving cavity (43; 430) having a lock cavity (41; 420); an adapter having a nose portion which is generally shaped to fit inside of the adapter receiving cavity (43; 430); a lock (20; 200) rotatably positioned in the lock cavity (41; 420) to rotate between an unlocked position and a locked position, the lock (20; 200) including a slot (21; 210), characterised in that the nose portion of the adapter includes a post (10;120); and the slot of the lock is adapted to receive the post (10;120); and wherein, when the ground engaging tool (40; 400) is slid onto the nose portion of the adapter such that the nose portion is inside of the adapter receiving cavity (43; 430), the post (10; 120) is adapted to be received in the slot (21; 210) such that rotation of the lock (20; 200) does not cause the post (10; 120) to rotate, and wherein, when the ground engaging tool (40; 400) is slid onto the nose portion of the adapter such that the nose portion is inside of the adapter receiving cavity (43; 430) and the post (10; 120) is received in the slot (21; 210), the lock (20; 200) in its locked position is adapted to prevent the post (10; 120) from sliding out of the slot (21; 210) and to prevent the ground engaging tool (40; 400) from sliding off of the adapter, and, when the lock (20; 200) is rotated to its unlocked position, the post (10; 120) is adapted to slide out of the slot (21; 210), and the ground engaging tool (40; 400) and the lock (20; 200) are free to slide off of the nose portion of the adapter while the lock (20; 200) remains positioned within the lock cavity (41; 420).