What is claimed is the ornamental design for an extendable handle, as shown and described.
FIG. 1 is an upper-front-left 3D view of an extendable handle in a collapsed configuration;
FIG. 2 is a lower-front-left 3D view of the extendable handle of FIG. 1;
FIG. 3 is an upper-rear-right 3D view of the extendable handle of FIG. 1;
FIG. 4 is a lower-rear-right 3D view of the extendable handle of FIG. 1;
FIG. 5 is a left side elevational view of the extendable handle of FIG. 1;
FIG. 6 is a top side elevational view of the extendable handle of FIG. 1;
FIG. 7 is a bottom side elevational view of the extendable handle of FIG. 1;
FIG. 8 is a front side elevational view of the extendable handle of FIG. 1;
FIG. 9 is a rear side elevational view of the extendable handle of FIG. 1; and,
FIG. 10 is an upper-front-right 3D view of the extendable handle of FIG. 1 in an extended configuration.
The broken lines showing the plunger portion that is mounted to the extendable handle, are included for the purpose of illustrating environment, and forms no part of the claimed design.