That saves assembly time on a repair bench, but the full-pack construction also traps more heat inside the junction; the 25 W power dissipation ceiling at the case tells you the heatsinking still matters. Gate drive is specified at 10 V for the rated 480 mOhm on-resistance at 4.5 A, and the gate charge is 25 nC at 10 V, which is modest enough for a standard gate-driver IC or a simple PWM output from a controller.
Obsolete — planning the replacement now
If you are repairing a board that originally used this part, the replacement decision is the same: you need a pin-compatible N-channel MOSFET in a TO-220FP package with a 650 V drain-source rating and similar gate charge to keep the drive circuit happy. The base product number STF10N suggests a family; a direct functional equivalent from ST's current MDmesh™ portfolio would be a part with the same voltage class, similar Rds(on), and the same full-pack footprint. For volume production or new designs, this part should not be specified — move to an active MDmesh™ V or MDmesh™ K5 series device with matching ratings.
Sourcing a discontinued MOSFET — what to expect
Because the STF10NM65N is obsolete, the only supply route is the independent distribution channel — surplus stock, overstock from OEM contracts, or broker inventory. Availability and pricing vary by lot date code and quantity; each quote is confirmed at the time of the RFQ. There is no factory lead time to manage, but the trade-off is that you are buying from whatever remains in the open market. For a repair technician pulling a dead board, this is often the quickest path if you need the exact footprint and don't want to re-layout the gate-drive trace. For a procurement buyer managing a BOM line, the smart move is to qualify an active replacement and dual-source the remaining stock against the RFQ.