Quick Verdict
If you're deciding between these two industrial pumps, think first about the fluid and the system. The Cole Parmer Masterflex L/S Process Peristaltic Pump with 4-channel pumphead is a used peristaltic pump that handles multi-channel transfer at a $1,585 price. The 3\" x 2\" Durco Flowserve MK3 STD Chemical Process DCI Centrifugal Pump NEW Z1 is a new open-box centrifugal pump built for chemical process duty, priced at $2,750. The price spread is $1,165.
Between the two, the Masterflex is the pick for flexible, multi-line transfer work on a budget; the Flowserve is the pick for demanding chemical process service where a new open-box centrifugal pump is worth the higher cost.
Comparison Table
| Feature | Cole Parmer Masterflex | Flowserve MK3 |
|---|---|---|
| Listed price | $1,585 | $2,750 |
| Condition | Used | New - Open box |
| Pump design | Peristaltic with 4-channel pumphead | Centrifugal chemical process pump |
| Distinguishing spec | 4-channel pumphead (7535-04) | 3\" x 2\" size, 250 PSI @ 100°F |
Where Each Product Wins
- Cole Parmer Masterflex L/S wins on price, multi-channel flexibility, and the ability to run multiple tubes at once. That makes it a strong fit for flow control lines that need several fluid paths in one setup.
- Flowserve MK3 wins on new open-box condition, chemical process pump design, and the size and pressure rating that suit a dedicated chemical transfer line.
Product Notes
Cole Parmer Masterflex L/S Process Peristaltic Pump with 4-channel Pumphead
This listing from BioLabTek combines the Masterflex L/S pump (model 07575-50) with the 7535-04 four-channel pumphead. If your flow control setup calls for moving fluid through several tubes at the same time, the peristaltic design gives you that capability directly. The used condition is reflected in the listed price, and the seller includes a 60-day return warranty. Just keep in mind that the listing includes only the pictured components, so confirm the head, tubing, and any accessories match your intended use before committing. This is the lower-priced route into Masterflex L/S pumping if you can work within the used-market constraints.
3\" x 2\" Durco Flowserve MK3 STD Chemical Process DCI Centrifugal Pump NEW Z1
Bitter End Trading offers this Flowserve MK3 as new open-box surplus inventory. The 3\" x 2\" size and MK3 STD designation make it a specific chemical process pump, and the listing carries a 250 PSI rating at 100°F. For a process line that needs a centrifugal pump with that kind of pressure capability, this unit delivers the design you'd expect from a Durco Flowserve MK3 without the lead time of a full new-pump order. The listed price is higher than the Masterflex alternative. Be aware that the seller says there is no way to test the pump before sale, though they do offer a money-back guarantee if it arrives dead on arrival. That makes it a reasonable option if you have the inspection capability or are willing to accept slight uncertainty in exchange for a new open-box unit.
Final Choice by Use Case
Choose the Cole Parmer Masterflex L/S when your flow control work involves multiple fluid lines and a tight budget. Choose the Flowserve MK3 when your process needs a centrifugal pump with the pressure capability of a dedicated chemical process unit and you're comfortable with a larger up-front investment. There's no universal winner, only the pump that matches the specific duty you give it.
