The product is a manual pipe threader designed for creating BSPT 1/2" and 3/4" threads in pipes with outer diameters ranging from 15.88 mm to 26.9 mm. It features integrated internal and external pipe threading tools, making it a versatile and efficient tool for various pipe threading tasks. The model numbers P4112 and P4116 indicate the specific sizes and capabilities of the pipe threader, catering to different pipe sizes and standards in the industrial and business sectors.