5/16" size is smaller, it fits the screw in type, non-adjustable toe stop holes. 

• SOLD BY THE PAIR - Enough for one pair of skates.
• VARIETY OF COLORS - Available in many different colors to match your laces, wheels, or personal style. Or buy several pair and switch them up.
• REPLACE BULKY STOPS WITH THESE SMALLER DANCE PLUGS - Smaller and lighter than a traditional toe stop. Not recommended if you really use your toe stops for stopping or starting. But good if you never use the stops.
• INEXPENSIVE - A lot cheaper than traditional stops, but with genuine Sure-Grip quality built into every pair. Will work with almost any brand of skate.