this kind of cube connector is for 12″ x 12″ Protective Bolt Plate Utility Truss.
the cube plate is 8mm 
total sizes 12x12x12 inches /  the hole is 0.69 inch / two adjacent hole is 6.75 inch

section:Square300x300mm
Inclined tube: 25x2.0mm
Main tube:50x3.0mm
Braces:50x2.0mm
Material: Aluminum 6061-T6
This high-performance 300x300mm square screw lighting truss is the backbone of professional roof systems. Engineered from aerospace-grade aluminum, it provides a rigid, dependable structure for hanging medium-weight lights and audio gear. Perfectly compatible with modular stage systems, it ensures a safe and sleek foundation for any indoor or outdoor event.

Outdoor Customized Speaker Aluminum Truss Wings 2m Event Bolt Spigot Stage Truss Roof System 12x8x12m
stage deck 4x8ft height 1.2-2m with 2 stairs and stair handrails 9.76x7.32m

Aluminum Roof Bolt Truss System for Event Parties 13x13x7m (43x43x23ft) with 4 wings, each wing is 2m
 Modular Stage12.2x12.2m Height 1.6-2m (40x40ft) with 2 adjustable stairs

Aluminum truss spigot box corner, multi connection box truss
 
 

Heavy Duty Bolt Tube Aluminum Truss 6 Way Box Truss Corner Blocks for Exhibits And Displays
heavy duty type
 

Aluminum Stage Truss Accessory Corner Box Block Connector Interface Joint for Spigot Truss Event
heavy duty type

Aluminum Stage Truss Accessory Corner Box Block Connector Interface Joint for Bolt Nut Screw Truss Events
heavy duty type

Durable Aluminum Square Quad 6-way Multi Cube Connectors Junction Block for Screw Bolt Truss Box Corner
heavy duty type

An aluminum frame truss structure is perfect for events, concerts, and exhibitions. This structure can be used as a spigot bolt to attach to another structure, or as a standalone unit. It has an aluminum frame and is fitted with adjustable, easy-to-use truss, which is also aluminum. The truss is adjustable to any height, width, or length. 

This portable outdoor concert stage tent is perfect for outdoor events. The aluminum truss system provides strength and stability. The front and rear of the stage is open, allowing for easy access. The tent comes with a powder coated finish and is built to last.

Aluminum Bolt Truss with Hinges Section for Stage Tower
The Aluminum Bolt Truss with Hinges Section for Stage Tower is a specialized concert & event stage solution engineered for safe and efficient vertical tower deployment. This heavy-duty bolt truss system incorporates a precision-manufactured hinge section, providing a technically accurate pivot point that facilitates the controlled raising and lowering of large overhead grids and ground-support pillars.

Aluminum Music Portable Sound Professional Lighting Truss is a universal useful truss, it can be used as truss holder for sound system, also it shall be a lighting pillar or beam..