The standard badge fastener, is the pin.

BADGE FASTENER OPTIONS

Pin Fastener

Bulldog Clip $1.00 Additional

Magnet $1.00 Additional

Strap Lanyard $1.50 Additional

Cord Lanyards
$1.50 Additional

WARNING:
Magnets May Pose a Serious Health Risk for people with Pacemakers and ICDs.

Summary: 

Magnets may interfere with the operation of Pacemakers and Implantable Cardioverter Defibrillators, according to a study published in the December 2006 Edition of Heart Rhythm and other published Medical Journals.