MIWA WEST916.RA Unlocking the entrance door by not carrying the key

"Unlocking the entrance door by non-carrying a key"

It is an old 36-year-old five-story property without an elevator. Moreover, the site is on the 5th floor. (What was I doing 5 years ago?)

Climbing the stairs with my usual heavy tool bag was pretty hard.

The target door lock is MIWA RA type. The work was completed with normal unlocking.