Spacer spool is according witrh the API 6A and 16A, have ends connectors of same size, rated working pressure and design, spacer spool is wellhead sections which have no provision for suspension of tubular members and which may have no provision for sealing of tubular members. we can provide all size and pressure ratings suitable for wellhead extension, BOP spacsing, and choke, Kill and production manifold applications, spacer spool usually has the same nominal end connections, spacer spool identification consists of naming each end conenctin and the overall length(outside of end connection face to outside of end connection face)