Knowledge Base
The Buyer's Guide.
Practical articles on lens materials, coatings, sourcing and private label — written to help you spec better eyewear and buy smarter.
Welcome to the SunDefeat knowledge base. These guides are written for brand owners, distributors and retailers who buy eyewear at volume — not for end consumers. Each article focuses on the decisions that affect your cost, quality and margin.
Lens Material 101: PC, Nylon, Glass & Resin Explained
The lens substrate you spec directly shapes clarity, impact resistance, weight and unit cost. We compare polycarbonate, nylon, glass and resin so you can match the right material to your market segment — from budget fashion to premium optical.
Read the guide → Lens MaterialsProtective Polycarbonate Lenses: What Buyers Should Know
Polycarbonate is the default for sports and safety eyewear thanks to its impact resistance and light weight. Learn which certifications to request and how PC behaves in mass production, so your compliance claims hold up under testing.
Read the guide → CoatingsLens Coatings Guide: UV400, Anti-Scratch, Anti-Fog & Waterproof
UV400, anti-scratch, anti-fog and waterproof treatments change both performance and unit cost. Understand what each coating actually does and which combinations deliver the strongest value story for your buyers.
Read the guide → SourcingHow to Choose a Sunglasses Manufacturer: An OEM/ODM Checklist
Choosing the wrong factory costs you time, margin and brand reputation. Use this checklist to evaluate OEM/ODM partners on capability, compliance and communication before you commit to samples or a first order.
Read the guide → Private LabelPrivate Label Sunglasses: A Complete Guide for Brands
Private label lets you launch a branded eyewear line without owning a factory. Walk through the full workflow — logo, packaging, sampling and AQL inspection — so your first program runs on spec and on time.
Read the guide → Lens ColorsUnderstanding Sunglasses Lens Colors: G15, Grey, Brown & Gradient
Lens color is more than aesthetics — G15, grey, brown and gradient each filter light differently. Match the right tint to your target use case and market so your collection sells on function, not just fashion.
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