1) Place the unit flat on a table (do not fill while your dog is wearing the collar)
2) Hold the aerosol refill vertically (upside down)
3) Insert the tip into the filling valve and press lightly to remove any air that may be present. Release.
4) Reinsert the tip and press firmly for 10 seconds to fill the reservoir.
5) Release. Repeat the process to remove air.
6) Then press for 10 seconds once again to fill a second time.
7) Check the level of liquid by looking through the transparent casing of the reservoir.
Note: It is perfectly normal for a little of the product to escape during filling, however you should make sure you position the refill canister vertically in the correct manner and press firmly.