A tandem pulley includes a support bracket having the shape of an inverted U. The support bracket defines a through hole. A pair of sheaves is arranged in line inside the support bracket. Each sheave is mounted rotating freely around a spindle fixed to the support bracket. A carabiner is fitted in the through hole. A connector is configured to connect the support bracket with the carabiner. The connector is configured in such a way as to allow rotation of the carabiner around an axis parallel to the spindles of the pair of sheaves. A spring is connected to the support bracket, the spring being arranged to exert a force on the carabiner biasing the latter to a rest position by rotation of the carabiner.

A connection device comprises a connector forming a ring with an open position and a closed position. A handle is fixed to the connector and has two extensions receiving a user's hands. The handle defines a tube extending in a first direction and a through hole arranged to pass through the tube perpendicularly to the first direction. A first end of a wire member forms a loop fixed to the connector in the tube. The second end of the wire member is fixed to the user. The connector passes through the through hole and the loop to fix the handle and the wire member to the connector.

A linkless, locking snap-hook, comprising a body member with a proximal hook, defining a proximal opening facing a first direction, and a distal hook, defining a distal opening facing a second direction. A linkless, locking snap-hook also comprising a locking mechanism which has a keeper, a biasing means, and a locking grip member. The linkless, locking snap-hook is capable of accepting a variety of attachment devices.

A connection device comprises a connector forming a ring with an open position and a closed position. A handle is fixed to the connector and has two extensions receiving a user's hands. The handle defines a tube extending in a first direction and a through hole arranged to pass through the tube perpendicularly to the first direction. A first end of a wire member forms a loop fixed to the connector in the tube. The second end of the wire member is fixed to the user. The connector passes through the through hole and the loop to fix the handle and the wire member to the connector.

A carabiner includes a carabiner body having a first opening, a first gate coupled to the carabiner body, the first gate configured to open and close the first opening, and a second gate coupled to the carabiner body, the second gate, when closed, defining a first area and a second area and, when opened, providing a second opening to the second area. The first gate, when opened, provides a first opening to the first area. The first gate is configured to open via rotation in a first rotational direction and the second gate is configured to open via rotation in the first rotational direction.

A holder for a bit for a tool is provided. The holder comprises: a bearing shaped to securely hold the bit; and a housing attached to the bearing and to a clip. In the holder, when the housing is attached to the clip, the bit may be mounted to the tool and the tool may be operated to rotate the bit; and when the bit is removed from the tool, the bit is still attached to the housing which is still attached to the clip. The housing may be shaped and sized to provide a friction fit to securely hold the outer ring. A cable may attach the housing to the clip.

A 360-degree double carabiner includes an outer-carabiner, an inner-carabiner and a swivel joint including a swivel cylinder and two locking pins. The outer-carabiner is enabled into a horizontal hole, the inner-carabiner is enabled into a vertical hole, the two locking pins are enabled into two smaller holes of the swivel cylinder to lock the outer-carabiner and the inner-carabiner to the swivel cylinder. The 360-degree double carabiner includes an outer latch, wherein one end of the outer latch is fixed to a proximal end of the outer-carabiner and another end of the outer latch rests on a distal end of the outer-carabiner. The 360-degree double carabiner includes an inner latch, wherein one end of the inner latch is fixed to a proximal end of the inner-carabiner, another end of the inner latch rests on a distal end of the inner-carabiner.

A connecting component with built-in radio frequency identification element which includes a main body and a radio frequency identification element is provided. The main body has a cylindrical body part and a head, wherein the body part has a connecting end and a free end; the head is connected to the connecting end, and the maximum outer diameter thereof is greater than an outer diameter of the body part; the head has an accommodating hole, and an opening of the accommodating hole is formed at a top of the head; the radio frequency identification element can be inserted into the accommodating hole. When the connecting component is used to fixedly connect the rigid object, the radio frequency electronic component provides a space to store database; with the radio frequency identification reader, industry can read the data at any time during the inspection or the maintenance stages, which improves the convenience of obtaining data and the efficiency of operation.

A gear sling device comprises a body in the form of a hook with an opening and a gate fixed to the body. The gate is fitted movable with respect to the body between a first position closing the opening and a second position leaving the opening open. The body and gate define a ring. A loop is designed to fix the body to a belt of a harness or to a strap. The loop is partly bounded by the body. The gear sling device comprises a wire-like element fitted sliding inside a through hole passing through the body. The wire-like element extends from the through hole to a pressing area where a first end of the wire-like element pulls on the body. A clamp is configured to block the wire-like element and to define the size of the loop.

A safety hook includes a hook body having an opening, a pivoting portion and a latching portion. A composite link includes a fixing rod and a guiding post. The fixing rod is pivoted at the pivoting portion, and the guiding post has a positioning portion, a sliding groove and a fastening portion. The guiding post encloses the opening through the fastening portion fastened with the latching portion. A rotating kit includes a sleeve and a pin, and the sleeve sheathes the guiding post and coupled to the composite link. A resilience component is sleeved outside the fixing rod and abutted the sleeve. The composite link is restricted when the sleeve is pushed by the resilience component.