450 x 450 png 1kB
Source:https://best-clipart.com/free-shapes-clipart.html

791 x 1024 gif 5kB
Source:http://www.okclipart.com/Rectangle-Clip-Art30yvokdiwp/

2400 x 2400 png 24kB
Source:http://www.okclipart.com/Rectangular-Clip-Art30cvunjpyz/

541 x 700 gif 1kB
Source:https://yourgraphicsprofessor.wordpress.com/2013/11/12/art-222-tr-notes-111213/

5846 x 4134 png 213kB
Source:http://www.worksheeto.com/post_likes-and-dislikes-worksheet-esl_377653/

250 x 250 png 2kB
Source:https://best-clipart.com/free-shapes-clipart.html

1600 x 1200 jpeg 12kB
Source:https://www.talkbass.com/threads/realist-soundclip-review-tips.766595/

640 x 480 0kB
Source:http://singletrackworld.com/forum/topic/whose-great-idea-was-it-to-have-a-mohammed-cartoon-competition/page/2

1132 x 667 png 31kB
Source:http://dsnursery.blogspot.com/2016/01/week-of-jan-25-29.html

618 x 194 jpeg 4kB
Source:https://laurelwilko.wordpress.com/visual-communication/

618 x 194 jpeg 7kB
Source:http://joystudiodesign.com/rectangular/rectangular-border.html

304 x 304 png 17kB
Source:https://www.abcteach.com/documents/clip-art-shapes-rectangle-color-labeled-i-abcteachcom-22964

296 x 147 png 0kB
Source:http://www.clker.com/clipart-382268.html

247 x 320 gif 1kB
Source:https://jeopardylabs.com/play/enter-title188880

300 x 300 jpeg 1kB
Source:https://clipground.com/azure-blue-clipart.html

640 x 480 121kB
Source:http://www.okclipart.com/Vertical-Rectangle-Shape-Clip-Art30wyxfbzbe/

299 x 165 png 0kB
Source:http://www.clker.com/clipart-green-rectangle.html

2400 x 1324 png 3kB
Source:http://openclipart.org/detail/82723/simple-green-rectangle-by-mireille

494 x 640 gif 3kB
Source:http://driverlayer.com/img/a%20rectangle/19/any

338 x 338 jpeg 4kB
Source:http://www.freepik.com/free-photos-vectors/rectangle-outline

880 x 340 jpeg 29kB
Source:https://clipartart.com/categories/rectangle-clipart.html

200 x 200 png 0kB
Source:https://www.mavericklabel.com/products/preprinted-labels/colored-labels/colored-rectangle-labels-three-by-five.html

190 x 180 jpeg 21kB
Source:https://classroomclipart.com/clipart/Clipart/Shapes.htm

618 x 361 jpeg 9kB
Source:http://www.teacherfiles.com/clip_art_shapes.htm

618 x 1253 jpeg 21kB
Source:http://www.teacherfiles.com/clip_art_shapes.htm

320 x 197 gif 5kB
Source:http://etc.usf.edu/clipart/38600/38617/rectangle_38617.htm