Reference 4500 is one of the very few Oyster chronograph models produced by Rolex featuring only a 30 minutes register but leaving out the 12 hours counter. This renders the watch a smoother, more subtle and less sporty design, a look that is usually rather found in Patek Philippe's celebrated reference 1463.
Reference 4500 was launched in the 1940s and was available in yellow gold, pink gold, stainless steel and in stainless steel and gold.
Different versions of this model are described and illustrated in I Cronografi Rolex - La Leggenda, Pucci Papaleo Editore, pp. 206 - 221.