Patent ID: 7866384

Claim:
A downhole device for incorporation into a downhole string and movement in a well-bore, the device comprising: a body member having a central longitudinal axis; at least one roller arranged on the device to engage an inner surface of the well-bore, the at least one roller comprising a running edge extending around an outer circumference of the roller and a portion configured to orient the device in the wellbore, the roller having a rotational axis perpendicular to and extending through the central longitudinal axis of the body member and perpendicular to the circumferential running edge, the roller being mounted on the device so as to permit the roller to rotate about its rotational axis relative to the body member; and wherein the portion of the roller configured to orient the device comprises a projecting portion of the roller which projects radially outwardly from the body member in a direction of the rotation axis of the roller, the projecting portion of the roller is shaped such that the projecting portion of the roller is eccentric to the body member.