https://www.suryaengineer.com/rebar-coupler.html#roll-thread-rebar-cou

Rebar couplers are used in reinforced concrete structures to replace normal rebar lap joints. The couplers are also suitable for use in reinforced concrete columns and walls. Each rebar coupler consists of a piece of rebar equipped with a thread and coupler sleeve at the right end as viewed in the direction of installation. In construction joints, rebar couplers can be used to replace all pieces of rebar going through the formwork. Our range of products include Taper Rebar Coupler, Cold Forged Rebar Coupler Type II, Steel Rebar Coupler, Cramping Rebar Coupler, MBT Rebar Coupler and Bar Break Rebar Coupler.
https://www.suryaengineer.com/rebar-coupler.html#roll-thread-rebar-coupler