Riser blocks allow you to remove your crumb tray and still get your material within focus area of your laser head. Can be used for all laser cutters.Blocks consist of 5 steps in 1/4″ increments. Holes in the bottom of the riser can hold a 5mmx3mm rare earth magnets if you like to add them. Magnets Sold separately (will not be installed, attach with glue) – 5mm x 3mmhttps://www.etsy.com/listing/1037544062/add-on-magnet-set-for-acrylic-tumbler **Includes ** 4x – Riser Blocks All items are 3D printed out of PLA+If using for a Glowforge you must remove the provided crumb tray before using these. Due to the nature of 3D printed items, there may be slight imperfections that will not affect the laser cutting