The Optimus D5 pump bottom acts as a large machined heatsink to wick away heat from the D5 pump itself, while also providing a massively ridged structure to dampen vibration and noise.
Satin Silver Anodized (Left)
Satin Pro-XL Nickel Plated (Center)
Satin Black Anodized (Right)
The satin silver and satin black match the Foundation block brackets as well as the silver and black fittings and silver and black GPU backplates. The nickel finish matches Signature CPU blocks and Shiny Pro-XL Nickel found on cold plates and fitting barbs.
Pump top can be rotated in any direction on the pump bottom
The Optimus Pump Bottom can only be used with Optimus parts
Some 3rd Party D5 pumps won't fit the pump bottom correctly (AC Next, for example) and non-official Xylem D5s. Premium D5s made by Xylem will fit perfectly