The SL is the Slider 1 inch a 1 inch wide sliding plate at the widest part.
The sizing refers to the amount of steel to make the shoe.
10 inch = 00
11 inch = 0
12 inch = 1
13 inch = 2
It is a steel unclipped shoe and packaged in pairs.
Available in sizes 10-13
Can be used with the Mustad Slider 4.5 Nail