Apparently the near trapezoidal with pinched short sides usb charger connection fits the Garmin, Motorola RAZR, moto Q [and Cannon Camera to transfer images]. However, the Garmin does not function reliably with an off brand cell phone car charger that fits in the charging slot. Is there a standard voltage or wattage [does amperage matter?] that all these devices use so a universal charger can be used?

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