Abstract: An apparatus for retaining a weight on a barbell includes a collar member and a weight engagement portion. The collar member has an annular rigid outer section and a radially inner frictional gripping portion, and defines an opening through the collar member to allow the collar to closely and slidably receive the end of the barbell. The weight engagement portion is associated with the annular, rigid outer section of the collar member in such a manner that axially outward movement of the weight or axially outward force thereon will contact the weight engagement portion and/or increase the force thereon, causing the axis of the collar member to skew and/or increase its skewedness with respect to the axis of the barbell, thereby frictionally locking the apparatus onto the bar. This frictional locking may also be achieved by skewing the aforesaid axes by hand, separate and apart from any contact between the weight and the apparatus.