Kyle Richards most definitely has a favorite accessory ... on Tuesday to share a shot of herself rocking yet another cowboy hat with a teeny bikini. She paired her woven Lack of Color hat ...

Kyle Richards was seen in Aspen, Colorado, over the weekend shopping with her estranged husband, Mauricio Umansky.

I'm just picturing Kathy naked with, like, fuzzy socks and a hat on," her sister Kyle Richards joked. OConnor/AFF-USA.com / MEGA Kathy has been married to her husband, Rick Hilton, since November ...