It helps prevent external dust particles from moving into the substantial-pace rotating supporter and touching the hash board.s19j Professional for sale d7 asic miner lt5 asic miner s17 pro 53th asic antminer s17+ bitmain antminer l7 9500mh t17e miner antminer t19 for sale lt5 mining antminer s9j price m21 56thFor quite possibly the most existing p