Identify the date of conception and the calendar marks the approximate birthing date and other events. 21.5cm x 21.5cm (8-1/2” x 8-1/2”) with a hole punched in the top corner so it can be hung anywhere. Digitally printed and feature great graphics. Printing is water resistant. Plastic material is durable in harsh conditions. Inquiries for customized Gestation Calendars are welome.