规定了开放式直幻灯片托盘（欧洲设计）的基本尺寸，用于符合ISO 1755的首选国际标称尺寸5cm×5cm的投影机幻灯片，容量为36张幻灯片或50张幻灯片。它包括一个用于检查托盘轮廓和齿轮系统的测试仪表。

Specifies the essential dimensions of a straight slide tray, open type (European design), for projector slides of the preferred international nominal size 5 cm × 5 cm complying with ISO 1755, with a capacity of 36 slides or 50 slides. It includes a testing gauge for checking the tray profile and gear system.