Suggested Size and Weight One unit of size equals about 3-4 centimeters. So a long key would be about 2 units in size. One unit of weight is around the same weight as one unit of water. So if you think about it, a jar of water (ignoring the jar weight) of size 15 would weight 15 units. A shirt is going to have a large size but a small weight, while platemail armor is going to have a large size and a large weight. These examples are estimates of what size and weight objects could have. It is up to the judgement of the builder to estimate a realistic size for the objects they are using. Item Size Weight arrow 10 4 throwing dagger 6 6 longsword 55 35 halberd 65 50 leather armor 43 15 cotton shirt 35 8 chainmail armor 50 32 platemail armor 52 52 wooden torch 20 12 gold coin 1 1 anvil 35 80