Oral irrigator housing

A housing for an oral irrigator having a hand piece includes a base unit having an upper and lower portion, the lower portion engageable with a support surface and having an upper surface defining a recess for receiving the hand piece, and the lower portion defining a peripheral shoulder. The upper portion extends upwardly from the lower portion and defines a top surface, the top surface defining a port and a key structure, the upper portion being positioned inside the peripheral shoulder. A reservoir has a bottom surface defining an aperture and sidewalls extending upwardly from the bottom surface to define a cavity having a peripheral rim, the sidewalls in part defining an indentation extending from the bottom surface up to a top end adjacent the peripheral rim at a position interior to the peripheral rim. A top wall extends from the top end of the indentation to the peripheral rim, the top wall forming an overhang. The bottom of the reservoir also defines a recess to receive the key formed on the top of the base unit for positional orientation during placement of the reservoir on the base unit.