The Omega Seamaster Cosmic Reference 165.023 (often cataloged with suffixes like SP) is a highly regarded 1960s vintage timepiece that beautifully captures the "Space Age" design ethos of its era.

• Water Resistance: While historically marked as "Waterproof," vintage monocoque cases from this era are considered splash-proof at best today. Avoid any exposure to water.

• The "Front-Loading" Design: Because the movement must be extracted via the front, it requires a specialized crystal lift tool (often noted on Cosmic case backs as "Tool 105" or "Tool 107"). This design keeps the movement isolated from pocket lint and dirt, meaning the caliber inside is often found in remarkably clean condition.

• Dial Authenticity: The silver dial variants of the Cosmic line are prone to redialing (refinishing) or heavy aging. Look closely at the typography alignment of "Seamaster Cosmic" to ensure it matches original catalog references if you are assessing its collector value.

• Brand & Line: Omega Seamaster Cosmic. 

• Reference Number: 165.023 (SP indicates specific dial/case finishing variants, such as polished steel). 

• Era: Produced in the late 1960s (typically circa 1967–1969). 

• Movement: Omega Caliber 552—a highly reliable, copper-colored, automatic (self-winding) mechanical movement featuring 24 jewels and no date complication. 

• Case Diameter: 33.5mm to 34mm excluding the crown (often wearing slightly larger due to the C-shape cushion case layout). 

• Lug Width: 18mm. 

• Case Construction: Unishell (Monocoque / Monobloc). The case is crafted from a single solid piece of stainless steel with a fixed back. Servicing is performed exclusively from the front by removing the plexiglass crystal. 

• Dial Variant: Silver dial, frequently featuring a fashionable vertical brushed finish or a subtle crosshair motif paired with applied baton hour indices.