Will these work with aftermarket wheels that have deep-seat lug nut holes?

L40 nuts are engineered for L40-pattern wheels. If your wheels specify a different lug nut pattern or seat type, these won't fit. Verify your wheel's lug nut requirement before ordering — it's usually printed on the wheel itself or in your wheel documentation.

Do I need to replace all lug nuts at once, or can I mix these with existing ones?

For safety and consistency, replace the entire set. Mixing different nut materials and styles can cause uneven clamping force across the wheel, which affects brake and suspension geometry over time.

Are these sealed or treated against corrosion?

They're anodized blue, which provides a protective finish. However, the open-end design means the threaded seat is exposed to salt and moisture. Periodic inspection and light cleaning help extend their life, especially in wet climates.