The Multiquip EM505719 Key 1/4" Sq. is a genuine OEM replacement designed for ST-45HRM and ST-70 submersible pumps. As a direct OEM part, EM505719 is manufactured to the same specifications as the original component, ensuring a correct, drop-in installation with no guesswork. This key is compatible with ST-45HRM and ST-70 series submersible pump units and is the part specified by Multiquip for service and repair of these machines.
Key Features
- Genuine OEM Construction — Manufactured to Multiquip's original dimensional tolerances, ensuring the key seats and locks properly in the keyway without slop or movement.
- Direct Drop-In Installation — Matches the 1/4" square profile of the original, slotting directly into the shaft and hub keyways without modification.
- Confirmed Fitment — Verified replacement for ST-45HRM and ST-70 submersible pump models.
- Positive Power Transfer — A properly seated drive key locks the impeller or drive component to the shaft, ensuring full torque transfer and preventing slippage under load.
- Protects Shaft and Hub — Using the correct OEM key prevents uneven wear on keyway surfaces, protecting the more expensive shaft and hub components from accelerated damage.
A drive key is a small but critical component that fits into matching keyways cut into a rotating shaft and the hub of an impeller or drive coupling, locking the two together so they rotate as a single unit. Without a correctly sized, properly seated key, the driven component can slip on the shaft — resulting in loss of pump output, vibration, and rapid wear to the keyway surfaces on both the shaft and the hub. Replacing a worn or damaged key promptly with the correct 1/4" square OEM part restores full torque transfer and prevents secondary damage to costlier pump components.
Part Details
| Part Number | 505719 |
|---|---|
| Brand | Multiquip |
| Part Type | Genuine OEM |
| Description | Key 1/4" Sq. |
Compatibility & Fitment
| Name | Model |
|---|---|
| Submersible Pumps | ST-45HRM |
| Submersible Pumps | ST-70 |
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.
