Ariel rescue kit

So when not working with a second climber who has their own climbing kit I have this kit set up ready to chuck in the van

The Petzl bucket bag comes in useful once again (35lt)

Harness at the top of the bag ready to put on straight away

Then side strop/second line and spikes

With the main line loosely stacked into the bottom of the bag with a blakes hitch pre tied. Attached to the harness are a couple of slings, some extra crabs and a folding knife, first aid kit is on the list of things to buy. 

Ant one else have a dedicated ariel rescue kit, or do you rely on spare/second climber kits?