SUNLU Refill PETG Filament 1.75mm 4-Pack - Durable PETG Refills

In this review the SUNLU Refill PETG Filament 1.75mm 4-pack is assessed for makers who already own reusable spools and want a cost-effective, reliable PETG option. The biggest reason to consider these refills is straightforward: they deliver PETG toughness and smooth printing at a lower per-kilogram cost when reused with compatible spools. The kit includes black, white, grey and transparent 1kg refills and is aimed at users who can transfer filament onto SUNLU or Bambu Lab reusable spools before printing.

Key Features

• Refill format: Designed for use with SUNLU and Bambu Lab reusable spools, this format cuts material waste and lowers ongoing filament cost.
• PETG blend: Combines the toughness of PETG with ease-of-use similar to ABS, giving parts improved durability and reduced brittleness.
• Compatibility: Works directly with SUNLU and Bambu Lab reusable spools and can be adapted to custom printed spools for most desktop 3D printers.
• Printing stability: Engineered to reduce stringing and clogging, helping produce smoother surface finish and consistent extrusion.
• Vacuum packaging: Each refill is sealed in airtight vacuum packaging to keep the filament dry and preserve printability until use.
• Recommended settings: Suggested printing range helps you dial in good results: nozzle 240-260C, bed 60-70C, speed 50-200mm/s.

Who It's For

This refill pack is best for hobbyists, small workshops, and makers who already own SUNLU or Bambu Lab reusable spools and want to reduce costs. It suits users printing functional parts that require higher impact resistance and toughness, such as brackets, enclosures, and durable prototypes.

It is not ideal for someone who needs a ready-to-print spool out of the box or a beginner who prefers plug-and-play convenience; buyers without reusable spools will need to acquire or print a compatible spool before these refills can be used.

Pros & Cons

Pros

• High toughness and impact resistance make printed parts durable for functional use.
• Economy refill format lowers material cost when you reuse compatible spools.
• Smoother printing profile with reduced stringiness helps with surface finish and fewer clogs.
• Secure vacuum packaging preserves filament quality and prevents moisture issues.

Cons

• Cannot be used directly from the pack; requires an empty compatible reusable spool or a printed spool adapter.
• Some reports show mixed results for adhesion and stringing depending on printer setup and slicer settings.

Specifications

Filament type	PETG refill
Diameter	1.75mm
Spool weight	1kg per refill
Pack contents	4 colors: black, white, grey, transparent
Recommended nozzle temp	240-260C
Recommended bed temp	60-70C
Packaging	Vacuum sealed

Our Verdict

The SUNLU PETG refill 4-pack is a sensible buy for users who already use reusable spools and need durable, impact-resistant filament at lower cost. It delivers reliable print quality and reduced stringing when tuned correctly, and vacuum packaging helps maintain performance, making it good value for makers focused on functional parts rather than instant plug-and-play convenience.

Frequently Asked Questions

Can these refills be used directly on a printer?
No, the refills must be loaded onto an empty reusable spool from SUNLU or Bambu Lab, or a compatible custom spool, before printing.

What printing settings work best?
SUNLU recommends 240-260C nozzle temperature, 60-70C bed temperature, and speeds between 50-200mm/s; tune retraction to manage stringing.

How is moisture handled?
The filament is vacuum packaged to stay moisture-free during transit; store unopened until needed and consider a dryer if moisture is suspected after opening.