
Rola-Chem Lock Knob Assembly for RC303/305/307 Peristaltic Pumps
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Quick overview
- Rola-Chem part 523408 The factory lock knob assembly for the RC303, RC305 and RC307 pumps.
- Holds the roller housing shut The knob is what clamps the pump head cover down over the squeeze tube.
- Three pump models Listed for the RC303, RC305 and RC307 peristaltic feeders.
- Not for every Rola-Chem The source listing states it does not fit the RC252 or the RC301 pump.
- Common wear item Knobs get cross threaded or snapped during tube changes, and the pump head will not seal without one.
- Sold as an assembly Supplied as the complete knob assembly rather than a loose thread insert.
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Lock Knob Assembly for RC303/305/307 Peristaltic Pumps
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Product details
The Rola-Chem 523408 is the lock knob assembly used on the RC303, RC305 and RC307 peristaltic chemical feed pumps. It is the knob that clamps the roller housing cover closed over the pump head.
Why it fails
The knob comes off every time the squeeze tube is changed, and that is exactly when it gets cross threaded, over tightened or dropped. Once the knob will no longer draw the cover down tight, the tube is not pressed properly against the rollers and feed rate falls off or the head leaks.
Check the model first
This knob is listed for the RC303, RC305 and RC307. The source listing specifically states it does not fit the RC252 or the RC301, so confirm the model on the pump label before ordering.
| Brand | Rola-Chem |
|---|---|
| Manufacturer part number | 523408 |
| UPC | 757706001878 |
| Type | Lock knob assembly |
| Fits | Rola-Chem RC303, RC305, RC307 peristaltic pumps |
| Does not fit | Rola-Chem RC252, RC301 |
| Ships | Parcel |
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