Spectacle Blinds are generally applied to permanently separating pipesystems, or just to connect with each other. Spades and Ring Spacers are basically the same as Spectacle Blinds, except that both are not attached to each other.
Carbon Steel: A 516 Gr 60 /65 / 70
Stainless Steel: A 240 TP 316
Duplex Stainless Steel: A182 Gr F51 / F53 / A240 UNS S31803