Well-Nuts with Stainless Steel Screws, 20 pack
[HDW-WN-20PK (6U8)]

Used these to secure my Anchor trolley, and a few deck fittings. Will be replacing everything else with them as need be. They make replacing broken fittings a snap, and you dont have to drill out rivets to remove broken pieces. They are AWESOME!! Save yourself time, money and frustration, get these to start with!!