Threaded square hole plugs for tubes

These plugs for square tubes have a threaded hole through the centre to accept a jacking screw or threaded foot for adjustment.Depending on their manufacture, the surface of the plastic cap can be more or less rough.

此款方形管用插头中心设有螺纹孔，以容纳千斤顶螺栓或螺纹底座进行调节。根据其制造工艺，塑料帽的表面可能相对较为粗糙或细腻。