A hook assembly (100, 900) comprising: a first portion (110, 820, 910) and a second portion (120, 830, 920), each of the first portion and the second portion being rotatably joined at a rotary joint (170, 820, 940) at respective joint ends (160,162) thereof, the first portion and the second portion each defining a perimeter shape (330,340) wherein the first portion and the second portion define (a) an enclosed orientation when the joint is in a first rotational position with respective free ends of the first portion and the second portion in a confronting relationship so as to form an enclosed interior shape and (b) a hook orientation when the joint is in a second rotational position rotationally remote from the first rotational position; and wherein the joint includes an index assembly that selectively maintains the first portion and the second portion in each of the first rotational position and the second rotational position with movement therebetween by application of predetermined rotational torque at the joint: wherein the index assembly includes an axle (570, 880), a first index surface interconnected with the first portion having at least one male projection, a second index surface interconnected with the second portion having at least one female detent, and a spring assembly that movably biases the first index surface toward the second index surfaces, and allows movement of the first index surface away from the second index surface under compression of the spring assembly, characterised by the first index surface and the second index surface each being rotatably positioned on the axle (570, 880). a first portion (110, 820, 910) and a second portion (120, 830, 920), each of the first portion and the second portion being rotatably joined at a rotary joint (170, 820, 940) at respective joint ends (160,162) thereof, the first portion and the second portion each defining a perimeter shape (330,340) wherein the first portion and the second portion define (a) an enclosed orientation when the joint is in a first rotational position with respective free ends of the first portion and the second portion in a confronting relationship so as to form an enclosed interior shape and (b) a hook orientation when the joint is in a second rotational position rotationally remote from the first rotational position; and wherein the joint includes an index assembly that selectively maintains the first portion and the second portion in each of the first rotational position and the second rotational position with movement therebetween by application of predetermined rotational torque at the joint: wherein the index assembly includes an axle (570, 880), a first index surface interconnected with the first portion having at least one male projection, a second index surface interconnected with the second portion having at least one female detent, and a spring assembly that movably biases the first index surface toward the second index surfaces, and allows movement of the first index surface away from the second index surface under compression of the spring assembly, characterised by the first index surface and the second index surface each being rotatably positioned on the axle (570, 880). wherein the index assembly includes an axle (570, 880), a first index surface interconnected with the first portion having at least one male projection, a second index surface interconnected with the second portion having at least one female detent, and a spring assembly that movably biases the first index surface toward the second index surfaces, and allows movement of the first index surface away from the second index surface under compression of the spring assembly, characterised by the first index surface and the second index surface each being rotatably positioned on the axle (570, 880).