Abstract: A spike cluster adapted for attachment to the bottom of an athletic shoe includes a body having a concavity in its upper face with a rim at the periphery of the upper face surrounding the concavity. Means are provided on the upper face of the body for attachment thereof to the bottom of a shoe. A plurality of spikes are located near the periphery of the lower face of the body and extend downwardly therefrom. Each spike has a vertical bore therein, open at the bottom and acting to provide improved traction, particularly on wet surfaces. A protrusion on the lower face within the area bounded by the spikes also extends below the lower face. The cluster may be secured to the bottom of an athletic shoe with the rim providing a clamping surface around the upper margin of the cluster for frictional engagement with the bottom of the shoe. Thus, movement of the cluster relative to the shoe under the stress of use is resisted. The protrusion acts as a shedder to prevent accumulation of dirt between the spikes.

Abstract: A detachable spike assembly for shoes includes the combination of a spike element which is threaded at one end thereof and is tapered at the other end. A laterally-extending flange is provided integral with the spike element intermediate the ends thereof. An annular element is rotatably secured to the spike element between the flange and the threaded portion.

Abstract: Gripper element for sports shoes especially for track shoes for use on plastics tracks, in which the element is provided with a body having one or more sharp penetrating surfaces adjacent the free end of the element and one or more support surfaces at a greater angle to the axis of the element, the support surface or surfaces preventing undue penetration of the element into a plastics track. A preferred construction comprises a body having the shape of a half barrel in which are formed a plurality of grooves the depth of the grooves increasing gradually from the free end of the element to a point approximately at the center of the length of the element and then gradually decreasing, the grooves forming the penetrating surfaces and the support surfaces.