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Post mix is a premixed 20kg concrete for setting fence posts, letterboxes, clothes lines and garden posts — just add water in the hole. Approx. 10L yield per bag. Delivered Australia-wide by Retaining Walls Direct.
Written and product-checked by the Retaining Walls Direct team — supplying retaining wall and fencing materials across Australia. Last updated: June 2026.
A convenient premixed concrete for post-setting jobs around the home and on site. For setting retaining wall steel posts in a hurry, see our fast-setting rapid set instead.
| Size | 20kg bag |
|---|---|
| Yield | Approx. 10L per bag |
| Use | Fence posts, letterboxes, clothes lines, garden posts |
| Brand | Retaining Walls Direct |
Get a quote or contact the team.
How much does one bag set?
About 10L — roughly one standard post hole; check your hole size.
Post mix or rapid set?
Post mix for general posts; rapid set when you need it to set fast (e.g. retaining wall posts).
Can you deliver to me?
We deliver across most of Australia. Send your details for a quote.
