An apparatus for stabilizing a stationary trailer with an adjustable length leg member. The apparatus comprises a ground engaging base plate which is attached to the end of the adjustable length leg member and has attachment means for one or more stabilizing members. The first end of the stabilizing member attaches to the ground engaging base plate and the second end of the stabilizing member attaches to an attachment member depending from the trailer. The attachment member is adapted to slidably receive the second end of the stabilizing member and comprises locking means for engaging the stabilizing member and locking the stabilizing member with respect to the attachment member.