Abstract: A borehole conditioning tool suitable for use in a drill string, the tool including a tubular body portion having a plurality of elongated, circumferentially spaced retainer slots for housing wall contacting members, each retainer slot being defined by a pair of opposed elongated slot side walls and a plurality of wall contacting members in the form of elongated stabilizer blades which are mounted in the retainer slots, each stabilizer blade having a pair of opposed blade side walls. In the borehole conditioning tool the slot side walls and blade side walls are shaped so that for each stabilizer blade one blade side wall is in engagement with one slot side wall, while the opposed blade side wall is in engagement with the opposed slot side wall along only a portion of the length of the blade side wall in at least one interference zone, the degree of interference being sufficient to locate the blade in position in the slot.