The Multiquip 50101 Square Key 3/16" x 45 MM 5.5 HP is a genuine OEM component designed for MQ Mixers, Whiteman Mixers, Essick Mixers, and MRH Roller series equipment. As a direct OEM replacement, this square key is manufactured to the same specification as the original part, ensuring proper power transfer between the shaft and driven component. Verified fitment covers a wide range of models including MC64SK, MC64PK, MC64P/S, WM70S/P, MC44S, WM63H8, WM63H5, WM63E, EM70P/S, WM90PLF, WM90SLF, WM70PLF, WM70SLF, EM90SLF, EM70SLF, WM90S/P, EM90P/S, MRH800GS, and MRH601DS. When your square key wears or shears, replacing it promptly with the correct OEM part keeps your mixer or roller running at full capacity.
Key Features
- Genuine OEM Construction — Machined to the exact 3/16" cross-section and 45 MM length specified for 5.5 HP driveline applications, ensuring correct torque transmission without slippage.
- Drop-In Shaft Fitment — Sized to seat flush in the original keyway slot with no filing or shimming, restoring the shaft-to-hub connection as intended.
- Broad Mixer and Roller Compatibility — Confirmed fit across MC64, WM70, WM90, WM63, EM70, EM90 mixer families and MRH800GS and MRH601DS walk-behind rollers.
- Driveline Integrity Restored — A worn or sheared square key causes the drum or roller to slip or stop turning entirely; installing Multiquip 50101 restores full mechanical engagement immediately.
- Low-Cost Preventive Component — Replacing this small but critical part at first sign of wear prevents accelerated damage to the shaft, hub bore, and drum drive assembly.
A square key is a small precision-machined piece of metal that sits in a machined slot — called a keyway — cut into both a rotating shaft and the hub of the component it drives, such as a mixer drum or roller drum. By locking these two parts together rotationally, the key transmits engine torque directly to the driven load. Because the key is designed to be the weakest link in the driveline, it will shear under shock loads before damage reaches the shaft or hub. When a square key shears or wears, the shaft simply spins inside the hub with no power transferred, causing the drum or roller to stop rotating despite the engine running normally. Replacing the key with the correct OEM part — matched to the exact shaft size and engine output — restores full driveline engagement and protects the surrounding components from further wear.
Part Details
| Part Number | 50101 |
|---|---|
| Brand | Multiquip |
| Part Type | Genuine OEM |
| Description | Square Key 3/16" x 45 MM 5.5 HP |
Compatibility & Fitment
| Name | Model |
|---|---|
| MQ Mixers | MC64SK/MC64PK |
| MQ Mixers | MC64P/S |
| Whiteman Mixers | WM70S/P |
| MQ Mixers | MC44S |
| Whiteman Mixers | WM63H8 |
| Whiteman Mixers | WM63H5 |
| Whiteman Mixers | WM63E |
| Essick Mixers | EM70P/S |
| Whiteman Mixers | WM90PLF |
| Whiteman Mixers | WM90SLF |
| Whiteman Mixers | WM70PLF |
| Whiteman Mixers | WM70SLF |
| Essick Mixers | EM90SLF |
| Essick Mixers | EM70SLF |
| Whiteman Mixers | WM90S/P |
| Essick Mixers | EM90P/S |
| Rollers | MRH800GS |
| Rollers | MRH601DS |
Verify Before You Order
Fitment is machine-number and revision-specific; always confirm your model and serial number against the fitment list.
Why Buy From DHS Equipment
Every part is verified against the manufacturer's part number before it ships, so what you order is what arrives. We carry parts from leading OEM brands and our own DHS Quality Parts line of professional aftermarket components. Need help finding the right part? Our team is available to confirm compatibility whenever you need it. Orders are processed fast to keep your jobs on track. We don't just sell parts. We keep you jobsite ready.
Questions? Contact our team at [email protected] or 866-611-9369 — DHS Equipment is here to help you maintain peak performance.
