Advertising tags on train handrails

Spotted these advertising tags on the Singaporean trains (MRT). They have little cut-outs at one end to enable them to hand on the overhead hand rails.

Cite
	Title:	Advertising tags on train handrails
	Author:	Liew, Zern
	Blog Title:	Thoughts at the intersection of Design, Business, Technology, and Applied Psychology
	Date:	8 May 2008
	URL:	https://eicolab.com.au/2008/advertising-tags-on-train-handrails.html