Sonnax Transmission Driveshaft Slip Yoke, 1350 U-Joint, 31 Spline, Tremec TKX, TKO
 

I bought this new in November, 2023 and ran it on my truck with a Tremec TKX transmission for about 500 miles. I am upgrading from a 3" driveshaft to 3.5", and the company I ordered the driveshaft from said it would void the warranty if I supplied the slip yoke. I'm buying another of the exact same kind from them and selling this one. These sell for $172 new.
https://www.summitracing.com/parts/SOX-T3-3-2491HP

Chromoly

$125 shipped - SOLD ON EBAY