Silva Expedition 4 Rotatable Navigation Compass 1:25k/1:50k

The Silva Expedition 4 is a full-size, rotatable baseplate compass engineered for advanced navigation with 1:25k, 1:40k and 1:50k map scales, durable construction and night-visible markings.

Built for mountaineers, search-and-rescue teams and serious backcountry navigators, the Expedition 4 combines a large, easy-to-read capsule with map-measuring scales, a magnifier and silicon friction feet so you can plot courses accurately in demanding conditions. It integrates declination adjustment, a sapphire jewel bearing for steady needle action and luminous elements for limited night use—everything needed when precision matters more than convenience.

How does the Expedition 4 help me plot accurate map bearings?

The rotatable housing and clear baseplate let you align the compass to grid north and read bearings directly against standard topographic maps. Internal declination adjustment allows you to correct for magnetic variation without estimating, and the printed 1:25k, 1:40k and 1:50k scales speed up distance measuring.

• Rotatable capsule for direct bearing transfer from map to terrain
• Built-in declination adjustment for precise true-north readings
• Map scales in mm and inches for 1:25k, 1:40k, 1:50k maps
• Silicon rubber feet keep the baseplate steady during plotting

What features make this compass durable and reliable outdoors?

The Expedition 4 is engineered with rugged materials and a sapphire jewel bearing that minimizes friction and keeps the needle stable after shocks. A detachable lanyard and robust housing protect the instrument in packs or on harnesses, while the liquid-damped capsule reduces needle wobble for quicker, more confident readings.

• Sapphire jewel bearing for long-term needle stability
• Robust housing and detachable lanyard for secure carry
• Liquid-damped capsule for fast needle settlement
• Night-luminous markings for limited low-light navigation

Can I use the Expedition 4 for night and low-visibility navigation?

Yes—selected markings on the dial are luminous after exposure to light, providing several hours of visibility for twilight or short nighttime legs. The large, clear capsule and magnifying lens also help identify gridlines and map details when light is poor, though it’s best used alongside a headlamp for long overnight routes.

• Luminous dial markings that glow after light activation
• Large magnifying lens for reading map detail in low light
• High-contrast red/black north-south lines for fast orientation
• Works best paired with a headlamp for extended night use

How does the Expedition 4 fit into advanced navigation systems?

The compass is compatible with Silva’s established navigation principles and can be used with grid-and-magnetic conversion techniques required for professional tasks. Its readable scales, rotatable housing and reliable needle performance make it suitable for training, detailed route planning and coordinated field operations.

• Compatible with standard grid-to-magnetic navigation workflows
• Clear baseplate and scales for distance and bearing calculations
• Patented red/black orientation lines to simplify map alignment
• Sized for glove-friendly use without sacrificing precision

Who is this for? The Silva Expedition 4 is aimed at experienced outdoor professionals and committed adventurers who need a dependable, feature-rich compass for complex navigation. If you lead multi-day routes, perform search-and-rescue tasks, instruct navigation courses or simply demand trustworthy map-and-compass performance in harsh conditions, the Expedition 4 delivers the tools and durability to get you where you need to go.