The Bexar County Jail does not allow mail supplies to be sent to inmates. All supplies must be bought from commissary. The Jail commissary carries stationary, envelopes and stamps. It may seem that the Sheriff’s Office is just trying to make more money off of the inmates but this is actually a safety issue. Various drugs can be soaked into the paper. The glue on the envelopes and stamps is another place that drugs can be added. You can add money to an inmate’s commissary so he can buy stationery and other items.