A shelf power supply system has a power supply track and a first power taking head and a retractable power supply track, the first power taking head has an external wiring. The retractable power supply track has a first moving part electrically connected to the external wiring and a second moving part being electrically connected with the first moving part and slideable thereon. The second moving part has a terminal. The invention can solve the problems that the wiring is complex and difficult to hide in the power supply system of the low-voltage lamps installed in the shelves and the laminates, suitable for the shelf support arms with different lengths, the size is small, the operation is very convenient, and one track can power multi-layer lamps, avoiding complex winding in the shelf, which is very simple operation and convenient for hidden installation in the shelf.

A combined type shelf includes column assemblies, first horizontal constraint assemblies, second horizontal constraint assemblies and storage layers. The column assembly includes assembly holes. The first horizontal constraint assembly has a first horizontal-constraint connecting fastener including horizontal-constraint hanging structures and rivets. The horizontal-constraint hanging structure engages the assembly hole to connect the first horizontal constraint assembly to a front or rear side of the column assembly. The second horizontal constraint assembly includes a horizontal-constraint hole to engage the rivet so as to connect the second horizontal constraint assembly to a left-hand or right-hand side of the column assembly. In addition, the storage layers are disposed between these column assemblies.

A combined type shelf includes column assemblies, first horizontal constraint assemblies, second horizontal constraint assemblies and storage layers. The column assembly includes assembly holes. The first horizontal constraint assembly has a first horizontal-constraint connecting fastener including horizontal-constraint hanging structures and rivets. The horizontal-constraint hanging structure engages the assembly hole to connect the first horizontal constraint assembly to a front or rear side of the column assembly. The second horizontal constraint assembly includes a horizontal-constraint hole to engage the rivet so as to connect the second horizontal constraint assembly to a left-hand or right-hand side of the column assembly. In addition, the storage layers are disposed between these column assemblies.

In a wall-mounted shelving and/or storage system, vertical standards are mounted to a wall using a plurality of individual cleats arranged in vertical columns and horizontal rows. The width of each cleat is smaller than the width of the standard, so that it can be hidden within the standard when mounted. Formed on the back of each vertical standard are a plurality of transverse edges at predefined intervals, in known spatial relationships with bracket connection points, for cooperating with the cleats to properly position and orient the standards at the correct height with respect to each other.

In a wall-mounted shelving and/or storage system, vertical standards are mounted to a wall using a plurality of individual cleats arranged in vertical columns and horizontal rows. The width of each cleat is smaller than the width of the standard, so that it can be hidden within the standard when mounted. Formed on the back of each vertical standard are a plurality of transverse edges at predefined intervals, in known spatial relationships with bracket connection points, for cooperating with the cleats to properly position and orient the standards at the correct height with respect to each other.

Quadrangular shelving comprising four bars with sets of four first pairs of holes, wherein the location of said sets defines different heights of the shelving for establishing the quadrangular trays, a set of quadrangular trays, wherein each tray comprises four corners and wherein each corner forms an opening and comprises a second pair of holes, the shelving comprises for each tray of the set of quadrangular trays: four plates, a pair of screws adapted to screw each plate and wherein the plate covers the opening.

Quadrangular shelving comprising four bars with sets of four first pairs of holes, wherein the location of said sets defines different heights of the shelving for establishing the quadrangular trays, a set of quadrangular trays, wherein each tray comprises four corners and wherein each corner forms an opening and comprises a second pair of holes, the shelving comprises for each tray of the set of quadrangular trays: four plates, a pair of screws adapted to screw each plate and wherein the plate covers the opening.

The technology described herein includes a four-column shelving unit. One or more improved tie bars run between the front and rear shelf-support beams. The one or more tie bars are installed perpendicular to the shelf-support beams. The improved tie bar may take the overall form of a V-channel with a novel tri-notch connection on either end. The tri-notch connection allows the tie bar to connect with a front shelf-support beam on one end and a back shelf-support beam on the other end. The tri-notch connection includes two bottom notches and a top notch. The top notch may form a gap in the V-channel that allows the end of the tie bar to slip under a shelf-support flange on a shelf-support beam during installation. The two bottom notches are sized and shaped to receive an upward facing retention flange located on the bottom flange of the shelf-support beam.