Two protrusions prevent the laptop from sliding when it's at an angle. They seemed short to me. I attached clothespins to them to add height and it works. All I can say is that my particular laptop is not the right size for this particular machine. I don't know but it worked.
27" Monitor LG 27UL500, 3840x2160, 60Hz, IPS, black/white
23 Review
π» GIKERSY Adjustable Height Laptop Stand - 1.5" to 20", Ergonomic Sit to Stand Laptop Riser for Desk - Compatible with MacBook Pro, Dell XPS, Lenovo, HP & More 10-17" Laptops
12 Review
MoKo Universal Laptop Stand Bundle - 4 Pack Anti-Slip Silicone Elevation Stand for Tablets, Laptops, and Keyboards - Gray
12 Review
Graphic tablet XPPen Star 06C black/light green
20 Review
10.3" Lenovo Tab M10 FHD Plus 2nd Gen TB-X606F (2020), RU, 2/32 GB, Wi-Fi, Silver
47 Review
Backpack Xiaomi Mi City Backpack 2 dark gray
38 Review
Xiaomi Classic Business Backpack Blue Backpack
56 Review
16" Apple MacBook Pro 16 Late 2019 3072x1920, Intel Core i7 2.6 GHz, RAM 16 GB, DDR4, SSD 512 GB, AMD Radeon Pro 5300M, macOS, RU, MVVJ2RU/A, space gray
58 Review