Wow, 40 V, 116 Amp? http://www.yoycart.com/Product/43432394428/
About $2.88 in small quantities as I recall, but I've never used this distributor.
Please confirm MXP43P9AT, TO-220 case.
No help from Digi-Key parameter search.
IRL40B215 maybe. International rectifier, unless this is an automotive application.