With reflective Scale slip ring at one end of each Stepping Stone, with ring Slots on the Inner side of a Lower Cylindrical portion.That Fit Knurled Surface irregular Stepping Stone, and Reflective portions on the Inner Face of a Cylindrical portion, and external slots.

摘要

A Ladder which comprises a pair of vertical beams, a Plurality of horizontal Parts extending between and Connecting the beamsEach piece has a Plurality of transverse grooves provided on an outer Periphery thereof and extending in the axial direction thereof; and a reflector placed on by LOne end of each piece or less in a portion of transverse connection between each piece and the respective transverse Beam,Each reflector is in a Ring shape and a Plurality of irregularities is formed on an inner Periphery of a small diameter the same as aporcion acoPla in slots of each piece and transverse portions of the reflector formed irregularly on the internal Periphery in a large diameter portion of the same,And a Plurality of Slots formed on an outer Periphery of the reflector and extending in the axial direction of the same.