Made of steel metal the 1/2" small key rings are split rings. They are great designed hardware fastener for your keys, small accessories, tools, straps and lanyards etc.
Keychain - Wikipedia
Key Rings: Wholesale Keyrings: Metal, Steel, Plastic, Nylon, Polyester & Fabric Key Holders
Spro Power Split Rings provide a reliable, high strength connection for various heavy duty rigging applications. These split rings are perfect for reliably connecting hooks to hard baits and open easily with any pair of split ring pliers. They are extremely strong and corrosion resistant for a connection you can trust when trophy fish are on the line.
Spro Power Split Rings, 6 - 150 lb
KINGFOREST 100pcs Key Rings 1 inch, Key Rings Metal Keychain Rings Split Keyrings Flat Ring for Home Car Office Keys Attachment
Double-Ended Neck Lanyards With Quick Release Plastic Buckles
30pcs Flat Key Rings Key Chain Metal Split Ring (Round 3/4 inch
304 Stainless Split Ring –
Rogue Nylon Keychain
Bulk Key Rings Bulk Split Rings - Ball Chain Mfg
5/8 Oval Head Trigger Snap Hooks: For Round Cords and Flat Straps
YHYZ Split Key Ring Circle Assorted, Metal Round
1/2 Circular Swivel Ring Lobster Claw Snap Hooks: For Round or Flat Rope
The split nickel key ring by Make Market is for connecting jewelry parts such as leather material, key chains and more. These key rings don't require soldering because they work like key chain rings.
ArtMinds Split Nickel Key Ring - Each
1 1/4 Nickel Split Key Ring, Hobby Lobby
1/2 Circular Swivel Ring Lobster Claw Snap Hooks: For Round or Flat Rope