I started writing up a magus with a tool belt, and went back to look up their history. We’ve had one in a game supplement before, but it was disguised, because the wearer, like many at the time, was a woman.
Western tool belts begin with female roman slaves. They carried a little tool pouch on their belts, which contained personal hygiene items and domestic tools. The belt pouches carried on historically until they hit the Middle Ages. Again, they tend to be feminine because of the gendered division of labour. Men, speaking loosely, work with large tools that emphasise strength. Women, and here we are speaking in a very general way, did more domestic duties, using smaller tools based on manual dexterity. You can carry small tools in a belt pouch, but not large tools. Keys join these tools after the development of turn locks.
Once keys and locks become cheap, the belt pouch transforms, in some paces, into the chatelaine. A chatelaine is one of my favourite pieces of jewellery. It’s a belt plate from which hang several short chains, each of which is attached to a tool used in the daily work of the woman. These were a symbol of authority in senior servants, because it meant that the wearer was trusted with the keys to the valuables of the house or castle.
Modern tool belts, are for people using several tools in the same job without a break to swap tools. This is more common in modern, larger, quickly built structures.
Individual tools and materials have been defined but there is no Shape and Material Bonus already published for chatelaines or tool belts. My suggestion is Rego +5 for all of those keys, and the control they represent.
Games From Folktales 