There are quite a few grid patterns, but this one is a super tiny grid with some dust for good measure.
Source Dominik Kiss
A seamless background pattern with impressed gray dots.
Source V. Hartikainen
Prismatic Geometric Pattern Background 2
Source GDJ
To get the tile this is made up from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Prismatic Curved Diamond Pattern 4 No Background
Source GDJ
Prismatic Isometric Cube Extra Pattern No Background
Source GDJ
The file was named striped lens, but hey – Translucent Fibres works too.
Source Angelica
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
This makes me wanna shoot some pool! Sweet green pool table pattern.
Source Caveman
Remixed from an image that was uploaded to Pixabay by CatherineClennan
Source Firkin
A nice and simple gray stucco material. Great on its own, or as a base for a new pattern.
Source Bartosz Kaszubowski
A seamless chequerboard pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i. Alternative colour scheme.
Source Firkin
Inspired by a pattern found in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Black brick wall pattern. Brick your site up!
Source Alex Parker
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
Number 1 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Derived from an image that was uploaded to Pixabay by Kaz
Source Firkin
Prismatic Polka Dots Mark II 2 No Background
Source GDJ
Dare I call this a «flat pattern»? Probably not.
Source Dax Kieran
Prismatic Abstract Geometric Background 4
Source GDJ
Dark pattern with some nice diagonal stitched lines crossing over.
Source Ashton