An anti-theft device monitors objects having a shaft, strap, or similar element. The anti-theft device is comprised of a housing hingably connected to a cover. The housing and cover can move from an open position to a closed position to enclose the shaft or similar element. The housing has a first latch component and contains electronics including an arming switch on its top. When the housing and cover are moved to the closed position, the cover changes the status of the arming switch. The cover has a second latch element which combines with the first latch element on the housing to hold the housing and cover in the closed position. The anti-theft device may be armed or disarmed by a handheld remote. The latching elements may be releasably lockable and may be released by a magnet. The anti-theft device may have passcode protection capabilities.