Omega Speedmaster Professional Sapphire Caseback
This is the case back that is typically found on pre moon speedmaster professionals st145 012 and st145 022.
Omega speedmaster professional sapphire caseback. For the first professional models of speedmasters omega switched to a single angle beveled design for the case back. The second variation swaps out the solid caseback for a display back and the hesalite crystal for a sapphire crystal earning it the nickname the sapphire. While hesalite can be formed into different shapes with ease sapphire can only be cut and polished from a solid block into its finished shape. The stainless steel bracelet has an omega double deployant clasp and is relatively comfortable to wear.
The speedmaster moonwatch professional. This omega speedmaster professional moonwatch features a black dial covered by a scratch resistant sapphire crystal and graced by a small seconds sub dial 30 minute recorder and 12 hour recorder along with a central chronograph hand. The first is the traditional version that uses a stainless steel caseback and a hesalite acrylic plastic crystal. Today omega offers their classic manually wound speedmaster professional moonwatch in two different configurations.
An omega speedmaster with a sapphire crystal comes with a sapphire display caseback hence it s also called sapphire sandwich. This omega speedmaster professional moonwatch sapphire sandwich reference 311 30 42 30 01 006 was released in 2014 and has been in production ever since.