Aluminum Focus Marking Ring
For Preston HU3, arri wcu-4, & arri SXU-1 handunits
This new product is a blank aluminum focus marking ring for the Preston HU3 handset. It also fits Arri WCU-4 and SXU-1 handsets. If you’ve ever had a problem with the white plastic Delrin rings being near-impossible to put on or remove from the handset when it’s cold out, it’s because Delrin has a higher coefficient of thermal expansion than aluminum—it shrinks in the cold more than the metal HU3 knob.
These marking rings are machined aluminum in a natural silver colour and matte finish (they are clear anodized). They can be directly written on with Sharpie marker and wipe clean with Pancro or alcohol. Pre-marked lens mapping labels can also be purchased from Preston and applied using the alignment pinhole, making these perfectly compatible with the stock Preston pre-marked plastic rings.