I purchased (2) 6 " R&L1/4 20 threaded & (1) 8" R 1/4 20 threaded attaching aluminum discs. The payments somehow unexpectedly went through PayPal from my card which worked out ok. There were unfavorable comments in some reviews about problems with their communication, and products being available. I found none of these to be true. Excellent products arrive in a timely manner. Customer service excellent.