I don't understand the purpose of having this pole base. The button I think is a bulldog but its a push button. The west side of the GTA uses these different mounting doohickeys as seen on the signal on the left.
Looks similar to what Massachusetts uses for their state-owned guide signs here. Here's a pic. RIDOT use uses U-channel poles for guide signs off the freeway (and some on the freeway) like this.
LOL yeah they look a little weird. I think the cast aluminum breakaway bases look nice with traffic signals. The traffic signal poles here are not breakway though so if they get hit they don't go anywhere. They can get hit pretty hard and all that happens is a dent is left with a little bit of colorful scratches that match the paint color on the car that hit it.
I kinda like the giant cast aluminium transformer bases that NYC uses. The Polefab poles have built in breakaway bases but I've seen one with a cast base before.
Massachusetts used those transformer bases on their older signal installations here. Connecticut uses transformer bases for all of their freeway lights. BTW, that last link is right on the RI-CT line. The davits in the background are RIDOT davits with 250W HPS M-250R2s with PCs. CT DOT uses all tapered ellipticals and trusses on breakaway transformer bases with lights on relays. Their lights are also 250W HPS (at least in the rural area bordering RI) and they have quite a variety of lights! That's because they had been spot replacing failed mercs with HPS since the late 70s to early 80s so by the time they went all HPS, there actually weren't that many lights left to swap out. They currently use 115s and 125s.
CT DOT also has a LOT of those button-face reflector signs hanging around. MASSDOT does too but RIDOT uses all-reflective signs and the older ones are just non-reflective.