7 Downhole tools for use in oil and gas wells, namely, downhole couplers, downhole release tools, downhole release joints, and downhole safety joints; wireline tools for use in oil and gas wells, namely, downhole couplers, downhole release tools, downhole release joints, and downhole safety joints; slickline tools for use in oil and gas wells, namely, downhole couplers, downhole release tools, downhole release joints, and downhole safety joints; downhole tools having opposing segments operable to connect and selectively disconnect from each other while conveyed within an oil and gas well; downhole tools for use in oil and gas wells, namely, downhole tools for connecting and selectively disconnecting opposing segments of a downhole tool string while conveyed within an oil and gas well; and downhole tools having opposing segments operable to selectively disconnect from each other to disconnect opposing segments of a downhole tool string while conveyed within an oil and gas well