. 
In order to perform as designed, metal connectors must be fastened with the fasteners specified by the connector manufacturer. The use of undersize or inappropriate fasteners is very common and may result in the structural failure of any such connection. If you see critical connections that you suspect are inadequately fastened, knowing where to look up the proper fasteners is very helpful.
Most metal connectors used in wood framing are made by Simpson Strong Tie. Download the catalogue.
Hanger nails have the number stamped on the head. Most are either 8d or 10d. Almost all metal connectors require min. 10d hanger nails, very few allow 8d hanger nails (A35 are the common exception).
- Some heavy-duty connectors call for specific nails.
- 8d vinyl coated sinkers used with joist hangers are common but improper. 16d vinyl coated sinkers used with joist hangers are technically improper, but widely considered acceptable.
- Connectors should be attached directly to framing, not against drywall.