This is left and right corner braces and pully supports for the Tronxy X5SA series, although may work well on other corexy brands and models. This design is intended to fit over the existing metal top connecting bracket at the corner for minimal disassemble to use these. factory design does not have any support for the top if the screw the pulleys ride on causing them to be pulled inward by the belt tension. that results in excess uneven stress on the pully bearings, uneven wear on the belts, and less reliable tension on the belts during operation. This brace should solve all those issues. you will need longer screws then factory for the belt pulleys at the front corners. The screws you will need are 5mm thread and 50mm length. about $3 for 2 at Ace hardware. Also depending on your printer, you may need a spacer in the pully stack to fill extra room. The file should be oriented for the best printing position already, I suggest tree supports if you use supports. These do fit snug on the frame and over the factory connecting bracket on the top of the frame. for reference the printer in the pic is a Tronxy X5SA-2E frame.
feel generous ? https://cash.app/$Dmills541

Creality

Ender 3 Pro

No

Yes

0.16mm

60% or more

you will need longer screws then factory for the belt pulleys at the front corners. screws are 5mm thread and 50mm length. about $3 for 2 at Ace hardware