Sure Grip Metal Stem 5/16 Dance Plugs x2 White

Formally called the Super X Dance plug – smaller 5/16″
Newer Power Plug larger 5/8″ and this is the more common size.
5/16″ fits Sure Grip plates Super X; Jogger; and Probe 5/16 style
5/8″ fits Sure Grip plates Probe 5/8; Rock; Avenger; Avanti; Competitor; Century; Classic; Cyclone; XK4; Laser; Power Trac; and Snyder;
Smaller version will fit the Super X plate where the larger 5/8″ plug will fit plates that use the standard adjustable toe stops. 
All made in the USA.