For Square Hole/ Shaft Repair Tool Bicycle Square Hole Central Shaft Fixing Rod | eBay
10x Honda Screw Grommets Expanding Nuts- M4 Screw & Fits into an 8mm Square Hole | eBay
Domqga Cage Nut Assortment Kit,50 Sets Cage M5 Nut M5x20 Screw Kit Nickel Plated Iron Metric Square Hole Rack Mount for Marine Yacht RV,Cage Nuts and Screws | Walmart Canada
What tool can I use to unscrew a screw with a square shape hole? I want something like an Allen wrench because it's blocked by the sink so there's very little space. -