Patent ID: 7876234

Claim:
A gauge to determine the depth of a trailer within a body of water, the gauge comprising: a hollow tubular member having a bottom and a top such that the top holds a first light bulb and a second light bulb thereon, the first light bulb emitting a first light when illuminated and the second light bulb emitting a second light when illuminated, the first light being of a different color relative to the color of the second light; a housing attached to the tubular member such that the housing has an opening; a switch disposed within the housing, the switch electrically connected to a source of electric power, such that the switch switches between a first state wherein the switch connects the first light bulb with the source of electric power and does not connect the second light bulb with the source of electric power, and a second state wherein the switch connects the second light bulb with the source of electric power and does not connect the first light bulb with the source of electric power; a post disposed within the housing, such that the switch is disposed within the post; and a float that slides along a length of the post and controls the switch such that when the float is at a bottom end of the post, the switch is in the first state and when the float is at a top end of the post, the switch is in the second state.