Water bottle cap
FIG. 1 is a side elevation view of a water bottle cap embodying the design of the present invention; 
     FIG. 2 is a bottom plan view of the water bottle cap of FIG. 1; 
     FIG. 3 is a top plan view of the water bottle cap of FIG. 1; 
     FIG. 4 is a side elevation view of a water bottle cap showing a second embodiment of the design of the present invention; 
     FIG. 5 is a bottom plan view of the water bottle cap of FIG. 4; 
     FIG. 6 is a top plan view of the water bottle cap of FIG. 4; 
     FIG. 7 is a side elevation view of a water bottle cap showing a third embodiment of the design of the present invention; 
     FIG. 8 is a bottom plan view of the water bottle cap of FIG. 7; and, 
     FIG. 9 is a top plan view of the water bottle cap of FIG. 7. 
     The broken-line showing of a water bottle in FIGS. 1, 3, 4, 6, 7 and 9 is for illustrative purposes only and forms no part of the claimed design.