Based on this product's specifications, here are some alternatives and similar models
Grand drawing T-tube Grand GR-0070, diameter 7 mm, adjustable length 46–70 cm
Summary description:
Grand GR-0070 drawing T-tube is a drafting accessory with a 7 mm diameter and adjustable length from 46 to 70 cm. Designed for precise line work and use with drawing instruments, it provides a stable guide for technical drawings, diagrams and layouts. Suitable for architects, engineers and students requiring controlled stroke width and repeatable measurements.