On Southwest Splendors, the guides have bug spray and sunscreen which will be offered and passed around each time you exit the bus. Don't bother bringing your own--this is one of the perks of doing this trip--they handle it all for you! The guides will also carry the bug spray in their backpacks if you decide you need it later or want to reapply.
Hi glassslipper2004,
It looks like your question has been answered so all I wanted to say is have a great time!!! We are headed out West next month and I can not wait.
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