Warranty and Assistance: Respected sellers could provide warranties or guarantees on used tools, offering consumers with satisfaction and defense in opposition to unexpected troubles. As of now, mining BTC with ASIC hardware beneath a hashrate under TH/s is totally unfeasible and worthless, but luckily we produce other SHA-256 based currencies https://simonhmkhc.blogminds.com/complete-guide-to-antminer-z15-profitability-35925905