This heavy duty in-line wire tensioner is a very popular choice in both the fencing and horticulture industries.
 
The heavy 3mm thick casing is hot dip galvanised providing a long life option. It is simple yet effective to install and tension plus no special tools are required, a simple adjustable spanner can be used to wind the square spigot, then simply install a retaining peg made from the wire. Re-tensioning at a later date if required is a simple matter of tweaking the radisseur.
 
These are designed for permanent wire systems in any gauge, lighter versions are available for electric fencing or lighter wire. It’s ideally suited to most gauges of wire in mild or high tensile.