The ornamental design for a sealantgun, as shown and described.
FIG. 1 is a perspective view, taken from the front, top, and right side of a sealant gun showing my new design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear front elevational view thereof;
FIG. 4 is a left side elevational view thereof;
FIG. 5 is a right side elevational view thereof;
FIG. 6 is a top plan view thereof;
FIG. 7 is a bottom plan view thereof;
FIG. 8 is an environmental front view of the sealant gun with a sealant tube.
FIG. 9 is an environmental font view of the sealant gun with an alternate sealant tube; and,
FIG. 10 is an environmental front view of the sealant gun with two boards.
The broken line showing of the sealant tube and two boards is included for the purpose of illustrating environmental structure and forms no part of the claimed design.