Odaily News According to market news, The Mining Pod blog program revealed that the U.S. Customs and Border Protection (CBP) is detaining certain imported Bitmain Antminers at U.S. ports of entry. The equipment involved is Bitmain's Antminer S21 and T21 series, which is Bitmain's latest ASIC mining machine series. Sources said that the FCC and CBP are not targeting other ASIC manufacturers such as MicroBT or Canaan. In addition to revealing that the FCC requested a freeze, U.S. Customs and Border Protection did not provide the affected parties with specific reasons for taking the action, nor did it specify how long the goods would be detained.