This is a group for slash fans to exchange snail mail. Members can send letters, postcards, packages, anything they like (which is legal!) Members are not required to send any particular type of mail.
The group includes international members! You're not required to send mail overseas, but remember that even a postcard is well-received and is pretty cheap to post.
This is a closed group. New members are taken by referral only.
Members are encouraged to send mail as often as they like. There are only two requirements for belonging to the group: that you send something to someone at least 8 times a year and that received mail be acknowledged. This can be one person 8 times, one thing to 8 different people, and any variation in between. Members are, of course, welcome to send more.
Members are required to acknowledge received mail in a timely manner. Members who consistently fail to post to the group announcing mail they've received will be asked to leave the group (based on sender reports to the group maintainer). This doesn't mean if you forget once or twice you'll be kicked out. Nor does this mean you're responsible for lost or late mail. But saying thank you is common courtesy and lets the sender know the mail didn't get lost along the way.