Abstract: A precision linear bearing is designed to minimize the points of contact, rolling and rubbing, to reduce particulates and FOD while ensuring stability and accuracy in a manner suitable for a clean room environment. The linear bearing comprises at least first and second bearing layers within a one-piece housing. Each bearing layer comprises at least three roller bearing spaced around the axial bore in a first plane within the housing, each roller bearing having an axis of rotation substantially perpendicular to the axial bore and projecting into said axial bore for engagement of a linear member extending through the axial bore. Each roller bearing suitably engages the linear member at a single point of contact. The layers are rotationally offset from one another such that the roller bearings contact different positions around the circumference of the linear member. The linear bearing may be configured to engage the inner surface of a cylindrical member.