Product Details
Color Details
Size DetailsFrequently Asked Questions
Are the Maui Jim KUPA'A MJ641 sunglasses available with prescription lenses?
What is the difference between SuperThin Glass and MauiBrilliant lens materials?
What size face do the KUPA'A MJ641 sunglasses fit?
How do I clean and care for my Maui Jim KUPA'A sunglasses?
What does Maui Jim's PolarizedPlus2 technology do?
What warranty and repair services does Maui Jim offer?
Compare With Similar Frames
How the Maui Jim KUPA'A MJ641 Sunglasses stacks up against the closest alternatives we carry.
- Lighter weight due to MauiPure lens material (vs. heavier SuperThin Glass)
- Better impact resistance for active sports
- Lower price point ($199–$240 vs. $283)
- Similar square shape and medium fit
- Comparable price range ($235–$261)
- Full PolarizedPlus2 lens technology
- Lower price point ($214–$223)
- Similar square frame styling
- Full PolarizedPlus2 technology
Read the full comparison
Maui Jim KUPA'A MJ641 vs. Similar Square Frames
The KUPA'A MJ641 sits in the middle of Maui Jim's square frame lineup, distinguished by its SuperThin Glass lenses and signature native pattern temple details. Here's how it compares to other popular square models in our collection.
KUPA'A vs. Red Sands MJ432
The Red Sands MJ432 is the most direct comparison—both are classic square frames with similar dimensions and styling. The key difference is lens material: the KUPA'A uses SuperThin Glass for maximum optical clarity and scratch resistance, while the Red Sands uses MauiPure, a lightweight plastic material that's nearly as clear but weighs significantly less. If you prioritize the absolute sharpest optics and don't mind a bit more weight, the KUPA'A is the better choice. If you want a lighter frame for active sports or all-day wear, the Red Sands delivers excellent performance at a lower price ($199–$240 vs. $283). Both feature full PolarizedPlus2 technology, so glare elimination and UV protection are identical.
KUPA'A vs. Castles MJ728
The Castles MJ728 offers similar square styling and a comparable price range ($235–$261), making it a close alternative. The main decision point is aesthetic: the KUPA'A's native pattern temple details give it a more distinctive Hawaiian-inspired look, while the Castles may offer a cleaner, more minimalist design depending on the variant. Both frames fit medium faces well and deliver the same PolarizedPlus2 lens performance. Check the specific lens material for the Castles variant you're considering—if it's also SuperThin Glass, the choice comes down to styling preference and frame color options.
KUPA'A vs. Onshore MJ798
The Onshore MJ798 is the budget-friendly option in this comparison, priced at $214–$223. It maintains the square frame aesthetic and full PolarizedPlus2 technology but typically uses a lighter lens material than SuperThin Glass. If you're new to Maui Jim or want to save $60–$70, the Onshore is an excellent entry point. However, if you've worn glass lenses before and know you prefer the superior clarity and scratch resistance, the KUPA'A's premium optics are worth the extra investment. The Onshore is also a good choice if you prefer a lighter frame for extended wear.
Our Recommendation
Choose the KUPA'A MJ641 if you want the best optical clarity Maui Jim offers in a square frame, don't mind a bit more weight, and appreciate the distinctive native pattern temple details. Choose the Red Sands if you want similar styling in a lighter, more impact-resistant package at a lower price. Choose the Onshore if you're budget-conscious but still want authentic Maui Jim quality and PolarizedPlus2 technology. All three frames are prescription-compatible and come with Maui Jim's 2-year warranty.
At a Glance
Maui Jim RED SANDS MJ432 Sunglasses
Pros:
- Lighter weight due to MauiPure lens material (vs. heavier SuperThin Glass)
- Better impact resistance for active sports
- Lower price point ($199–$240 vs. $283)
- Still features full PolarizedPlus2 technology
Cons:
- Slightly less optical clarity than SuperThin Glass
- Less scratch-resistant than glass lenses
- Fewer frame color options available
Maui Jim CASTLES MJ728 Sunglasses
Pros:
- Similar square shape and medium fit
- Comparable price range ($235–$261)
- Full PolarizedPlus2 lens technology
- Alternative frame and lens color combinations
Cons:
- May not feature the distinctive native pattern temple details
- Lens material varies by model (check specific variant)
- Less customer review data available for comparison
Maui Jim ONSHORE MJ798 Sunglasses
Pros:
- Lower price point ($214–$223)
- Similar square frame styling
- Full PolarizedPlus2 technology
- Lighter weight depending on lens material
Cons:
- May lack the premium SuperThin Glass option
- Different temple design without native pattern details
- Potentially different fit characteristics