80lb Heavyweight Cardstock is the standard for "solid" structural integrity.
The term "solid paper" in this context typically refers to the used as the structural base for the project shown in the video. Key Paper Specifications IMG_0622.MOV
If you are trying to replicate the "solid paper" look or structure from a tutorial with this file name, these are the standard materials used: 80lb Heavyweight Cardstock is the standard for "solid"
Based on available information, "IMG_0622.MOV" appears to be a video file that is often referenced in crafting and scrapbooking tutorials specifically related to the "Moving Parts Page Folio" series by Paper Phenomenon . Core Connection IMG_0622.MOV