Same length is not the complete fit specification
The two size-10.5 Cankton listings provide a useful example of why size alone is incomplete. This title names Pebble/Black without a width; the Black/Charcoal entry explicitly says Wide. Do not use a price comparison between them to substitute one for the other until the actual width choices are known.
If you are reordering, match the width on the old shoe’s label instead of relying on memory of how roomy Cankton felt. The manufacturer’s Relaxed Fit name is not a replacement for selecting the width that fitted you.
What changes from a boot purchase
Cankton is described by Skechers as an athletic work sneaker. For a role allowing low footwear, that is a distinct format from Pittsburgh or Lansing Mid. The lower upper may be desirable, but it does not satisfy a policy that specifies boots simply because the cap is steel.
A shopper whose main problem is wet conditions should compare documented water protection rather than buy another color of the same shoe. The Cankton title includes EH and Memory Foam wording but does not establish a waterproof membrane.
Use the variant for ordering, not invented performance differences
There is no basis here to call Pebble/Black more breathable, more durable or more comfortable than Black/Charcoal. The relevant differences available in the selection are the listed color, length and width information. Protective claims should stay tied to the actual style supplied.
If 10.5 is the right length but the shoe feels narrow, look for a confirmed wide option at that length. If the shape still conflicts with your foot, changing models is more informative than cycling through Cankton color listings.