A cable retention system for a power distribution unit includes a tether and a tether mount. The tether has an elongate portion and an attachment portion, and the attachment portion includes a channel therein. The tether mount has a base at a proximal end and a head at a distal end. The base is adapted to attach the proximal end of the tether mount to the power distribution unit. The tether is adapted to be secured to the tether mount by snap-fitting the head of the tether mount into the channel of the attachment portion.