Waterproof Binoculars and Optics

What do the numbers mean?

Model numbers on binoculars show magnification and size (objective lens diameter). In 8x42 binoculars, the 8 is magnification, and 42 is the objective lenses.

Choose your magnification

• 8x: Wider field of view
• 10x: Closer, more detailed look

Size

Size is based on the objective lenses (the second number)

• Compact: Under 30mm (8x25, 10x28); lighter weight
• Midsize: 30mm-40mm (10x30, 8x32)
• Full-size: Over 40mm (8x42, 10x50); brighter image but heavier

Best for your activity

Wildlife viewing

• 10x if watching animals from a distance
• Midsize if you want something more compact

Birding 

• Midsize or full-size models if weight isn't a concern
• 8x for a wider field of view to locate birds

Hiking or backpacking

• 8x or 10x magnification
• Compact size for easy packing