The colour of the bolt seal does not matter but I do asked lots of time if that is something they need to worry about such as that all bolt seals have to be blue or yellow or orange. You can use any colour you want and most will use the colour that matches their company colours but this again is just a personal choice.  Some companies are using security seals to go northbound or southbound so they might have a different colour to one is coming north and one is going south. They also might have a colour that is used to show that the trailer is empty and they can then just pick it up and haul it without having to worry if someone has put something in there. They can also though use just a plastic security seal as that will also show that the trailer is empty and if the plastic security seal is gone then they need to find out why and maybe even get another trailer seals.
Security Seal Colors
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