When you're shopping for bearings couplings power transmission components, a rigid shaft coupling is a simple-looking part that gets complicated the moment you have to match it to a shaft. Do you need a keyed bore? Set screws? A rated torque limit? The two couplings here are both 2" long and finished in black oxide, but they are aimed at different shaft profiles and carry different prices.
Quick Verdict: If your installation uses a keyed shaft and you want rated torque and speed figures, the Summit Collars RC-075-KW is the clear choice. If you want a wider coupling body with multiple set screws for a secure hold, the uxcell Shaft Coupling is the one to beat.
Side-by-Side Comparison
| Attribute | uxcell 7/8" Rigid Coupling | Summit Collars RC-075-KW |
|---|---|---|
| Price | $34.32 | $18.59 |
| Bore | 7/8" | 3/4" |
| Outside Diameter | 1-3/4" | 1-1/2" |
| Length | 2" | 2" |
| Set Screws | 4 | 2 |
| Finish | Black oxide | Black oxide |
Where Each Product Wins
- Summit Collars RC-075-KW wins when the shaft has a keyway and you need a coupling that lists maximum torque and speed.
- uxcell Shaft Coupling wins when you want a wide coupling body and don't need a keyway.
uxcell 7/8" Bore Rigid Coupling
This uxcell coupling is a good fit when you want a wider clamping surface on the shaft. The 1-3/4" outside diameter gives it a broader footprint than the Summit, and the four set screws give you more points to tighten down. That combination can be useful for a rigid connection where you want a solid grip. The main trade-off is the price: at $34.32, it is noticeably more expensive than the Summit. You're paying a premium for the wider body and the extra set screws. If your budget is limited or the shaft is keyed, this may not be the most economical route. But if you need a non-keyed bore with multiple set screws, this coupling delivers.
Summit Collars RC-075-KW
The Summit Collars RC-075-KW is engineered for keyed shaft applications. It comes with a keyway and lists a maximum torque of 1,420 in.-lbs. and a maximum speed of 3,450 rpm, so you have concrete numbers to plan around. That makes it a strong choice when you need a coupling with a defined power rating. The trade-off is that it is designed for a keyed shaft. If your shaft doesn't have a keyway, the keyway in this coupling has nothing to engage, and the holding relies on the set screws alone. That narrows its usefulness to keyed setups, which is exactly what it's built for.
Final Choice by Use Case: Match the coupling to the shaft you're connecting. If the shaft is keyed, the Summit Collars is the right part because its keyway and torque rating fit the task. If the shaft is a smooth bore that will be held by set screws, the uxcell's wider body gives you more surface to clamp. The comparison table above shows the exact bore sizes so you can confirm which one fits.
