Pole setting expanding foam - GIF

[Karl_H]

Sika post fix is a two-part, pre-proportioned polyurethane resin which when mixed produces an expanding foam. It has been specifically formulated and packaged to provide a lightweight, mix-in-the-bag, and fast-setting backfill for wooden, PVC and steel in-ground supports.
A 2-component, pre-proportioned polyurethane resin that produces an expanding foam for supporting mail box or gate posts
Suitable for all types of posts including wood, steel and PVC
Lightweight pouch replaces two 50-lb bags of post mix
No water or special tools needed
Sets in 3 minutes and cures in 2 hours

4 x 4 and 6 x 6 posts require 2 bags.

About $13 bucks bag at the big boxes