RSS-3 PVC Rooftop Pipe Support | 3-feet long pipe block that can be split into desired lengths

we have been using them for 3 to 4 years now in 6" pieces for supports for ac split systems on the roof as normally there is no room to mount the safety switches on the unit. I was also given some left over walkway material and we cut the material into 6" strips and set the supports on the strips that does not allow them to sit directly on the roof. We have done over 70+ of them like that.