Shepherd Hardware 9418 2-Inch Office Chair Caster, Twin Wheel, 5/16-Inch Stem Diameter, 75-lb Load Capacity, Black, 2 Count

Why I tried these casters

I keep a small stash of common hardware in the shop for quick repairs—glides, stem casters, leveling feet—because nothing derails a workday quite like a chair that gouges carpet or a shop vac dragging a broken wheel. I picked up the Shepherd 9418 casters as a general-purpose, 5/16-inch friction-stem replacement set to test on a few problem items: a wobbly office chair, a mid-century tea cart with tired casters, and an older shop vac that had snapped a wheel. After a couple of weeks of use across those three, I have a clear sense of where these 2-inch twin-wheel casters shine and where they don’t.

What you get and key specs

The Shepherd 2-inch casters I used are a twin-wheel, black plastic swivel design with a 5/16-inch diameter x 1-1/2-inch long friction stem. Clearance height is about 2-1/4 inches from the mounting surface to the outer wheel edge. Each caster is rated at 75 lb, and the pack includes two casters and two metal mounting sockets. The twin-wheel format increases the contact patch and lets each wheel counter-rotate slightly as you pivot, which helps reduce carpet fiber twisting.

That combination—common stem size, included sockets, and a very typical diameter—makes them a handy drop-in for a lot of ready-to-assemble furniture, office chairs, and lightweight carts.

Installation and fit

On the office chair, installation was straightforward: pull the old caster straight out, pop the new one in. Friction-stem fit is all about tolerance. On that chair’s existing sockets, the stems pressed in by hand with a satisfying click. On the shop vac, the receiving sockets were slightly tight; a light pass with 220-grit around the stem’s retention ring did the trick. If you’re not comfortable removing material from the stem, you can very gently ream the plastic socket instead. Either way, tiny adjustments go a long way.

For the tea cart, I used the included metal sockets. Those need a 3/8-inch hole bored roughly 1-3/8 inches deep. A simple trick helps: wrap masking tape around your drill bit to mark depth and leave a little “flag” to sweep away chips as you drill. Tap the socket in with a mallet (use a scrap of wood to avoid marring the rim), and push the caster home. Once seated, the stem holds securely and swivels smoothly.

One caveat: the 2-1/4-inch clearance height may raise or lower your furniture slightly compared to the originals. On the tea cart, the new wheels added about a quarter inch—no problem functionally, but worth noting if you’re matching a set or need a precise working height.

Rolling performance on different surfaces

• Low-pile carpet: This is where the twin-wheel design works best. The casters rolled smoothly and didn’t churn the carpet when pivoting. The chair felt stable and didn’t sink much, and directional changes were easy.
• Hard floors (laminate and finished maple): Rolling was fine, but these are hard plastic wheels and they can be noisy on hollow floors. They didn’t scuff my laminate, but plastic is less forgiving than soft polyurethane. If you have delicate hardwood, I’d pick a soft-wheel alternative.
• Shop floor with dust and debris: Twin wheels can straddle small grit fairly well, but any small hard wheel is susceptible to picking up debris. After vacuuming fine grit for an hour, the casters still spun freely, but an occasional string or tape edge did try to wrap between the wheels. A quick check and pull cleans it out.

The swivel action is light and predictable. There are no ball bearings in the wheel hubs—these are plastic-on-axle bushings—so while movement is easy, it’s not luxurious. For most utility furniture, that’s perfectly adequate.

Load capacity and stability

Rated at 75 lb per caster, a four-caster setup gives you 300 lb of theoretical capacity. In practice, I always derate for uneven floors and dynamic loads by 20–30%. That puts a typical four-caster piece comfortably around 200–240 lb total, which covers a fully loaded tea cart or TV stand and most office chairs with an average adult. If you plan to carry very heavy loads, step up to a larger diameter caster with a higher rating or a metal-wheel core.

Lateral stability is good for the size. Twin wheels help reduce that “tippy” feeling you sometimes get with small single wheels. On a tall, narrow piece like a bookcase on wheels, the wider stance of the twin wheels helped it track straighter when pushed sideways.

Build quality

The cups and stems are consistent, the swivel tolerances are clean, and the finish on the sockets is decent. The wheels themselves are hollow plastic. That keeps cost and weight down, but it’s still plastic—good for light to moderate duty, not a match for rugged commercial casters with polyurethane treads or metal cores. After two weeks of mixed use, I see no flat-spotting, no cracking, and no stem wobble. I wouldn’t put these under a rolling tool chest, but for furniture and light equipment they’re up to the task.

Compatibility checklist and sizing tips

Friction-stem casters live or die on fit. Before you buy (or install), I recommend:

• Measure the stem you’re replacing. A 5/16-inch drill bit makes a good go/no-go gauge for diameter; calipers are even better. For length, measure from the shoulder to the tip—these are 1-1/2 inches.
• Check the receiving socket. If your furniture has no socket, plan to use the included ones and bore 3/8-inch holes. If the existing socket is damaged, replacing it with the provided sleeve often solves alignment and retention issues.
• Confirm clearance height. At 2-1/4 inches, these can slightly change how high a piece sits. On a desk chair, that can alter ergonomics; on a cabinet, it can affect how doors align with adjacent pieces.
• Consider the floor surface. For carpet: yes. For hardwood: consider soft-tread wheels instead, or use floor-safe mats.

A small dab of silicone spray in the socket makes insertion easier and reduces squeaks. If removal is stubborn, a gentle pry with a flat screwdriver at the shoulder (protect the surface with cardboard) pops them out without bending the stem.

Use cases that suit these best

• Office and task chairs originally spec’d with 5/16-inch stems
• Ready-to-assemble furniture, TV stands, and bookcases that roll occasionally
• Lightweight carts for serving, plants, or AV gear
• Shop vacs and small shop equipment that were built with friction-stem wheels

I wouldn’t use them under heavy toolboxes, mobile workbenches, or anything you’ll roll over thresholds with significant weight. For those, larger diameter polyurethane casters with plate mounts are a better match.

Value

As a two-pack with included sockets, the Shepherd 9418 casters hit a practical spot for quick repairs and light-duty upgrades. You’re paying for compatibility and convenience. They install fast, they roll fine on carpet, and they bring a tired piece of furniture back to life without hunting for oddball hardware.

If your priority is silent rolling on hardwood or maximum durability under load, there are better (and pricier) casters out there. But those typically require different mounts or plate adapters. For a friction-stem, plug-and-play solution, these are cost-effective.

The bottom line

The Shepherd 2-inch casters did exactly what I needed: restore mobility to a few household and shop items with minimal fuss. Installation ranges from “push in and go” to “drill a clean 3/8-inch hole and tap in the included sleeve,” and the twin-wheel design is genuinely helpful on carpet. They’re not heavy-duty and they’re not floor-protectors for fine hardwood, but they’re sturdy enough for everyday furniture and light equipment within their 75-lb-per-caster rating.

Recommendation: I recommend these casters for light- to medium-duty replacements where you need a 5/16-inch x 1-1/2-inch friction stem, especially on carpeted floors. They’re easy to install, track well, and the included sockets expand your options for repair or retrofit. If you need quiet rolling on hardwood or higher load capacity, look for a soft-tread or heavier-duty alternative.