VW CV joint bolt. These CV bolts are common across VW CV joints on 1.8T cars with 6 speed manual transmissions and 2.0T cars after 2006. After 1992 VW moved to various inner CV joint designs depending on your vehicle, engine, and transmission combination. There is a shorter version of these same bolts (#22417) for the cars equipped with the tripodic style non-serviceable inner joints from 1999 on. Pre-1999 an 8mm short (#22365) and 8mm long (#12355) version were used. If you are unsure of which size bolt you need it may be best for you to go and take one off your car and measure before you order. Sold in sets of 6, 1 set required per axle.
If you're removing your driveshaft, you'll need an 10mm 12 point Allen star tool for the inner VW CV joint bolts, and the 30mm axle nut socket for the outer bolt. New axle nuts can be ordered as part #19331.