The Dunn & Watson Door Hold Backs, also known as Door Retainers are available in either zinc plated or stainless steel. The big difference between these two Door Hold Backs, other than their finish, is that the stainless steel fastener is also spring loaded to eliminate any rattles and is usually used in refrigeration trucks, as well as in standard trucks. The locks are basically used to hold fridge and truck doors open so that when you pull up to a dock and are ready to unload, you don’t need to worry about the doors swinging around. They are pretty much only used on refrigerated truck doors and standard truck doors, but you could use them for any application where you want to hold large doors open, for example a bike trailer. We also have a very simple Rubber Door Hold Back Fastener that comes in two parts – a male and female component and is used for lightweight doors. Lastly, we have our heavy duty Cast Door Catch that’s ideal for very large doors on trucks or coaches. Manufactured from cast steel with wide diameter springs it gives you a very strong positive lock without having to key lock the door.