They are easily applied with a screw and Phillips screwdriver. The screws are supplied with this item. Each spike has a tap on the bottom in which the screw is applied. 

Description and Specs:
height: approx. 2 inch, 55 mm
base diameter: 3/8 inch, 9.5 mm
material: nickel over zinc
finish: Silver nickel
color: Silver
screw type: inch 8-32, 1/4" length thread
shape: round cone
Bag size: 20 spikes