Size

Swing cam locks come in many different sizes

Diameter ; almost all are 3/4 ' diameter

Length ; The lock housing is measured from just inside the "lip" on the front face of the lock

to the inside of the swinging lock "cam"

Rotation

Rotation ; locks "rotate " either 1/4 turn (90 degrees)

or 1/2 turn (180 degrees)

Cams

cams are made in many different sizes

 with different bends ,

 and different ends  ( hook ends etc )