adjustable swivel screw jack base 1)material ;Q235 2)OD size:28mm,30mm, ... 3)solid and hollow bar adjustable swivel screw jack base we can offer the products to you as per ... Prompt Delivery Quality Approvals Small Orders Accepted1)name: swivel base screw jack 2)material:Q2353)ODsize:28mm,30mm,32mm, ... small volume, long lifespan,good fastening and antislip capacity, first choice for scaffoldings building