Linear Motion Rolling Guide Unit

A linear motion rolling guide unit comprising:

• a slider comprising a casing, and a pair of end caps respectively secured to ends of the casing and each having engaging projections formed thereon;
• and
• underside seals that are provided between the pair of end caps, have a function of preventing entry of dust, and have receiving holes formed therein, the engaging projections of the pair of end caps being respectively fitted into the receiving holes for securing the underside seal to the slider,
• each of the underside seals comprising fallout-inhibiting protrusions provided at ends in a longitudinal direction of the underside seal, and
• the slider comprising holding portions each having either a hole or a recess into which each of the fallout-inhibiting protrusions is inserted while maintaining a gap between an outer periphery of the fallout-inhibiting protrusion and the holding portions having either the hole or the recess when the underside seal is secured to the slider.