Table Top Fasteners,20 Pack Z Clips for Table Tops Included 60 pcs Screws,Adjustable Corner Braces for Wood Table Tops,Which L Brackets Use on Wood Table as Countertop Fasteners

Multiple boards. I have no idea where I would get a slab that big! Even if I could.... I don't think I could afford it. I used wooden clips that I made. This is a video I got that idea from, but there's others out there too. https://youtu.be/btPGtq0hYTE?is=T5L_WwWORqgUcaSU Honestly, I also added these in a couple spots that felt like they needed better attachment, but after it was too late for me to get a router in there. https://a.co/d/0ggyWtF5 It calls them z clips, but they are not. However, they are easy to use and should allow for wood movement if attached correctly. I think the big worry is about allowing wood movement across the grain., so you want whatever you do to allow that.