Actuatable seat valve and actuators for use therewith

A downhole tool that is connectible to a string of tubulars for positioning within a well, the downhole tool comprising:

• (a) an outer housing that comprises an uphole end, a downhole end and an inner surface defined therebetween, each end is connectible to the string of tubulars, wherein the inner surface defines an interior space with a first inner-diameter and the inner surface also defines a recess with a second inner-diameter that is larger than the first inner-diameter;
• (b) a sleeve that is positionable within the recess, the sleeve comprising an uphole end, a downhole end and a ramp defined therebetween that extends substantially the length of the sleeve, wherein the sleeve has a larger inner diameter towards the uphole end than the downhole end;
• and
• (c) a seat that is slidably positionable within the sleeve along the ramp, the seat defines at least one plateau section that is configured to receive and engage an equatorial portion of an actuator when the actuator is received by the seat.