12 Pack 20mm Button Compass for DIY Paracord Survival Bracelets, Camping, Hiking a ferrite core and a

a ferrite core and a Hall effect element

then we suggest placing a piece of rubber under the magnet to increase friction

Drop Forged Heat Treated Steel for Strength and Durability

Features small screw-type binding posts for easy access to all positions (Note: there aren't holes in the posts)

spring hook and ground lead

12 Pack 20mm Button Compass for DIY Paracord Survival Bracelets, Camping, Hiking a ferrite core and aThis 20mm compass features an easy to read dial that is excellent for both beginner compass users and experts alike. It is lightweight and the perfect compact size for building into paracord bracelets and other DIY survival gear. NOTE: This model is not liquid filled. Specifications: Material: Plastic Size: Approx. 20mm x 7. 5mm Weight: 1. 5g (0. 05 ounce)