There were two types of the older spikes. If I remember right, here's how the old ones worked.
Spike kind #1. (I think these were blue)
When off, both M+ and M- are tied to ground.
Spike kind #2. (I think these were red)
When off, both M+ and M- are tied to 12V.
No picture of those...
You can tell they're the old kind because they have no sleeve for the PWM cable to go in. You can imagine how much of a headache this was for teams. I remember we glued ours in place.
The current generation of Spikes are still blue, unlike their Victor counterparts.
Someone may correct me. I'm going off of my memory.
Speaking of old Victors... we're using the old red labeled 884 Victors this year because our electrical guy likes the sound of the fans more.
But as far as Spikes go... the blue ones are still legal. Red ones are not.