Produced alongside the 5402, the Audemars Piguet Royal Oak Ref. 4100 bears the same finish and vintage qualities of its larger brother in a very wearable 36mm case. These watches are slim and perhaps the perfect size for most men (and even women!). These 4100s offer phenomenal value in comparison to their larger brother and other jumbo steel sport models on the market. Please do not hesitate to reach out with any questions.