Description

Key Features

Reinforces 90° Joints

The Simpson Strong-Tie A21 angle adds a steel connection where toe-nailing or screws alone can fall short. It helps keep corners straighter and more consistent in wood-to-wood framing and repair work.

18-Gauge Steel Build

This connector is made from 18-gauge steel, which gives light-duty structural reinforcement without adding bulk. That makes it useful for compact joints where space is limited.

G90 Galvanized Finish

The zinc galvanized G90 coating adds corrosion resistance for general framing and repair applications. If the job sees more moisture exposure, Simpson also offers related ZMAX versions in this angle family.

Overview

Simpson Strong-Tie A21 2 in. x 1-1/2 in. x 1-3/8 in. Galvanized Angle is a compact framing angle used to reinforce 90-degree wood-to-wood connections. This is a framing angle designed for fastening wood members at a right angle. Model Number: A21. If you are tying a small post, plate, rail, blocking, or repair piece into another wood member, this connector gives you a cleaner and more reliable corner than angled nailing alone.

The A21 matters because it solves a common jobsite problem: small joints are easy to pull out of square during assembly, and they do not always hold up well when fastened with nails or screws alone. By adding formed steel at the corner, the connection stays more consistent and gains measurable load capacity. Based on Simpson Strong-Tie load data for the A21, the connector can deliver listed lateral and uplift values when installed with the specified fasteners, which is what makes it more than just a simple bracket from the hardware aisle.

This angle is made from 18-gauge steel and finished with zinc galvanized G90 coating. In practical terms, that means it is aimed at light-duty structural reinforcement, repairs, and general wood framing applications where you want added strength without stepping up to a larger, heavier connector. The compact footprint also helps when you are working in tight spaces or trying to reinforce an existing joint without a lot of room around it.

Size is a big part of why the A21 gets used so often. The connector measures approximately 2 in. x 1-1/2 in. x 1-3/8 in., with Simpson listing dimensions as W1: 2 in., W2: 1-1/2 in., and L: 1-3/8 in.. That small profile makes it a practical choice for trim framing, blocking, utility framing, shelving support, fence repairs, and general home or jobsite fixes where a full-size structural angle would be overkill.

Installation is straightforward, but it only performs as rated when you use the specified fasteners. Simpson lists the A21 for installation with 10d x 1-1/2 in. nails or #9 x 1-1/2 in. Strong-Drive SD connector screws, and their general note is to use all specified fasteners. That is worth paying attention to. Leaving holes empty may be fine for a temporary mock-up or a nonrated repair, but if you want the connector to do what the load table says it can do, fill it properly.

For corrosion resistance, this A21 uses a standard galvanized finish suited to many interior or covered applications and general framing conditions. Simpson also notes that some angles in this family are available with upgraded coatings or stainless options, but this specific A21 model is the Zinc Galvanized, G90 version. That makes it a solid choice for typical wood construction, while higher-corrosion environments may call for a different finish within the same product family.

Who is this for? Carpenters, remodelers, maintenance crews, fence builders, and serious DIY users who want a compact wood connector that installs fast and does an honest job of reinforcing a corner. It is especially useful when the connection needs to stay square, the parts are too small for larger framing hardware, or you are upgrading a weak joint in an existing assembly. If you need a small galvanized angle for wood framing, repairs, or reinforcement, the Simpson Strong-Tie A21 is the kind of part that quietly earns its spot in the truck or shop bin.

Keeps Small Framing Joints Square

The whole point of this angle is simple: make a right-angle connection straighter and stronger without taking up much room. On repairs and light framing, that is often the difference between a joint that just looks attached and one that actually stays put.

• Designed for wood-to-wood fastening at 90-degree connections
• Useful where angled nailing alone does not give enough consistency or reinforcement

Compact Size, Real Reinforcement

The A21 is small enough to fit into tight assemblies, but it still gives you a formed steel connection that improves the joint over nails or screws driven on an angle. That makes it a go-to piece for utility framing, blocking, shelving supports, and general repair work.

• 18-gauge steel construction balances size and reinforcement for light-duty structural use
• Approximate dimensions: 2 in. x 1-1/2 in. x 1-3/8 in.

Use the Right Fasteners and It Does Its Job

Connector hardware is only as good as the fasteners used with it. Simpson publishes specific nail and screw options for this angle, so if you want the listed performance, this is not the place to substitute random screws from the bucket.

• Installs with 10d x 1-1/2 in. nails or #9 x 1-1/2 in. Strong-Drive SD connector screws
• Simpson installation guidance: use all specified fasteners

Key Specifications

Type	Framing angle
Application	Fastening wood-to-wood
Material	Steel
Gauge	18 ga.
Finish	Zinc Galvanized, G90
Dimensions	2 in. x 1-1/2 in. x 1-3/8 in.
Fastener Size	10d x 1-1/2 in. nails or #9 x 1-1/2 in. connector screws
Packaging Quantity	1

Compatibility

Material Connection

Designed for wood-to-wood connections.

Approved Nail Option

Compatible with 10d x 1-1/2 in. nails for installation.

Approved Screw Option

Compatible with #9 x 1-1/2 in. Simpson Strong-Drive SD connector screws.

Built For

Carpentry Wood Framing General Contracting Remodeling Repairs Shelving Support Fence Repairs DIY / Hobbyist

Pro Tip

If you are using the A21 for a connection that actually matters structurally, do not leave fastener holes empty just because the bracket feels tight after the first couple of screws. Simpson’s published load values depend on using the specified fasteners in the full pattern.

Tool Nut’s Take

Tool Nut’s Take

Why the Simpson Strong-Tie A21 2 in. x 1-1/2 in. x 1-3/8 in. Galvanized Angle Still Earns Drawer Space

This is the kind of small hardware that saves a build from becoming a callback, because it makes a weak little corner into a real connection.

• Who it’s for: Carpenters, remodelers, maintenance techs, fence builders, and homeowners who need a compact wood framing angle for repairs or reinforcement.
• Why it stands out: It is small, simple, galvanized, and backed by real connector load data instead of guesswork. That is exactly what you want from a basic framing angle.
• Worth knowing: This is an 18-gauge light-duty connector, not a substitute for stepping up to a larger heavy angle when the job calls for more steel. Also, use the specified nails or connector screws if you want rated performance.

Common Questions

• What is the A21 used for? It is used to reinforce 90-degree wood-to-wood connections in framing, repairs, and general construction projects.
• What fasteners should be used with this angle? Simpson lists 10d x 1-1/2 in. nails or #9 x 1-1/2 in. Strong-Drive SD connector screws.
• Is this connector galvanized? Yes. The A21 uses a Zinc Galvanized, G90 finish for corrosion resistance.
• What size is the A21 angle? Simpson lists the A21 at 2 in. x 1-1/2 in. x 1-3/8 in.