The extra wide edge makes it easier to use the spool, especially in colder water with gloves. Holes along the edge give extra space to fix the end of the line through the spool and attach the double ender to secure it. Ordinary spools only offer holes along the side which are quite often blocked by the line wrapped on the spool and make it kind of hard to get the end through or find enough space to clip the double ender. The end of the line was reinforced with black plastic which makes it easier to find it and gives better control.
The different colors make it already easier to identify YOUR spool optically from others. On top of it you can easily use the wide edge and its holes to give YOUR spool an additional tactile difference without disturbing its use, so you can locate it even in low or no viz.