Prusa MK3S+ Fan Shroud Printed In High Temp Deflection PC-CF(Polycarbonate+Carbon Fiber)If you need one for MK3,MK3S Specify While Ordering..Tested Printing Continuously At 290c For About A Year..Upon Disassembly To Upgrade To Revo Hot End I Was Going To Change The Fan Shroud Thinking After All This Abuse It Would Sag/Disform A Little And Due To My Amazement It Looked The Same The Day I Installed It...Long Story Short I Figured I Will Offer Same Item Printed In Same Material For Sale...I Tune The Extruder For Each Roll Of Filament i Get To Ensure Proper Fitment...Ships With Square Nut Pre Installed...I Do Combine Shipping If You Buying More Then One..