SUNLU PETG Filament Refill 1.75mm 4KG - No-Spool Matte Grey Refill

In this review of the SUNLU PETG Filament Refill 1.75mm 4KG, the bottom line is straightforward: this refill is aimed at makers who want a durable, high-speed PETG option while reducing spool waste. The kit ships as four 1KG refill rolls intended for reusable spools and is notable for being compatible with many popular systems including Bambu Lab spools and SUNLU 2025 new spools. It is a practical choice for users who prioritize toughness and impact resistance in prints and who value the environmental benefit of less plastic from no-spool refills.

Key Features

• Superior Compatibility: Works with SUNLU 2025 new spools, Bambu Lab spools and most FDM printers including AMS and AMS Lite, making it easy to add to an existing workflow.
• No-Spool Format: The refill design eliminates single-use spools, reducing plastic waste and lowering environmental impact compared with traditional spooled filament.
• High Speed Printing: Enhanced fluidity allows printing up to 600mm/s when tuned correctly, useful for rapid prototyping and time-sensitive jobs.
• PETG Strength: Combines PLA ease of use with ABS-like toughness and high impact resistance, suited for durable parts that need to endure stress.
• Clear Installation: Reusable SUNLU 3rd spools are marked for alignment so refilling and installation are straightforward even for beginners.

Who It's For

The SUNLU PETG refill is ideal for hobbyists, small workshop users, and prosumers who already use reusable or compatible spools and want a resilient material for functional parts. It fits users who need parts with high impact strength and who may print across a range of speeds from moderate to very fast.

It is less suited to those who require pre-spooled, plug-and-play cartridges for enclosed or fully automated spool systems that expect a full standard spool, or users with the SUNLU 2rd detachable spool which is explicitly not compatible. Confirm your spool model before buying.

Pros & Cons

Pros

• Durable PETG formulation gives strong, impact-resistant prints suitable for functional parts.
• Compatibility with Bambu Lab and SUNLU 2025 spools and many FDM printers simplifies integration.
• Refill format reduces plastic waste and is a greener option than single-use spools.
• Wide recommended temperature and speed windows allow tuning for both quality and speed.

Cons

• Some customers report spool fit and winding issues, as the refill rolls function like half-spools and may require care when transferring to reusable spools.
• Not compatible with SUNLU 2rd detachable spool, so it requires confirming spool type before purchase.

Specifications

Material	PETG
Diameter	1.75mm
Pack Size	4 rolls, 1KG per roll (4KG total)
Compatibility	SUNLU 2025 new spool, Bambu Lab spool, most FDM printers, AMS, AMS Lite
Print Speed Range	30mm/s to 600mm/s (recommended settings vary with speed)
Recommended Temperatures	205-270C nozzle depending on speed; bed 70-80C

Our Verdict

The SUNLU PETG Filament Refill 1.75mm 4KG is a sensible buy for users who want strong, impact-resistant PETG and prefer a lower-waste refill system. It delivers versatile print speeds and good compatibility with common reusable spools, offering strong value for functional prints; just verify spool compatibility and be prepared to manage winding when transferring to reusable spools.

Frequently Asked Questions

Is this refill compatible with Bambu Lab printers?
Yes, the refill is listed as compatible with Bambu Lab spools and most FDM printers, including AMS and AMS Lite setups.

What temperatures and speeds are recommended?
Use a bed temperature of 70-80C; nozzle settings vary by speed: 50-100mm/s at 205-215C, 100-300mm/s at 240-250C, and 300-600mm/s at 260-270C with matching speed adjustments.

Will these rolls fit every SUNLU spool?
No, they are not compatible with the SUNLU 2rd detachable spool; confirm you have the SUNLU 2025 new spool or a compatible reusable spool before buying.