"TEC-HRO alu-tube" is a barrel sleeve for sporting rifles with a muzzle diameter of 24.0 mm and has a prism suitable for Anschütz front sight tunnels.
It is fastened by brass grub screws, which press directly onto the flat side of the dovetail milling of the barrel from above. As a result, the tilting alignment is immediately given, so that the sleeve can be attached repeatably after removal (e.g. for cleaning).
An internal steel pin ensured that the sleeve was always attached at the same length. Simply slide it on the barrel as far as it will go and then lock it in place.
For cleaning, we recommend every 500 - 1000 shots with a Plastic brush brush out. The easiest way to do this is when the powder has dried up (i.e. not directly after shooting - better before shooting!!)