This is a very high quality anodized aluminum adapter
Converts an M42X0.75 male thread to a M42X0.75 female thread
Precision Thread Conversion: This telescope adapter is designed with external threads at both ends of M42×0.75 T/T2 male thread and internal thread of M42×0.75 T/T2 female thread
Anodized Aluminum Material: All metal construction, which significantly extends service life of product; Lightweight aluminum construction effectively minimizes load on telescope accessories, making it well-suited for long time astronomical observation