The threaded engine core plug was stubborn to remove but then the installation of the heater was easy. I like the threaded design over the typical "frost" plug block heater that uses a toggle bolt and "O" ring which has a tendency to leak.
Northern MN can get chilly, this was Genuine Scoobie-roo part.
Getting the old plug out was a challenge. 14mm Allen socket, 1/2" braker bar and a 36" pipe.
Make sure to buy some high temp silicone before you pull the plug.
This part quality was excellent, fit was perfect.
Exactly as described. Subaru A0910AS100 Engine Block Heater
Works exactly as expected. Very simple and functional. Easiest when engine is out for head gaskets. Mild effort when engine still installed. Good product.