I need to lock off some diesel bowsers. These are basically diesel tanks on a trailer. The trouble I am having is finding a padlock that has a long enough loop but not too long as it gets in the way of other fittings. The loop needs to be a minimum inner height of 40mm but ideally no longer than 90mm and with a minimum inner width of 20mm. The hole in the fitting is 18mm so plenty of space to fit the loop through. The trailers will on the road or left outside in harsh remote places so the padlocks really need to be good in all weathers.

You can have a look at a couple of options depending on your security level requirements. These padlocks fit the measurement requirements you have and either of the locks would be suitable for use in harsh environments such as you describe. Both of the products can be produced in key differ or keyed alike versions to give you flexibility in how you grant access to the diesel tanks.

The Abus Eterna 41/50HB50 steel laminated padlock is a highly superior lock and is not to be confused with the cheaper alternatives you can now find on the market. Abus have developed a treatment process which gives their laminated padlock a long lifespan. They are of course keeping this treatment process highly secret but it does give a steel lock with high grade weather resistance and strength.

Alternatively where you need a higher level of security, the long shackle Abus Granit 37/55HB50 is suitable for prolonged periods outdoors. It comes with a cataphorectic coating ensuring it is fully weatherproof to marine grade standard. Ideal when taking your diesel trailers all over the country. The removable shackle feature also means it is so much easier to fit on those diesels tanks with restricted access.