A sex toy that uses a pattern of colors, shapes, numbers, symbols, or any combination thereof to provide depth measurement markings in inches or centimeters which are easily read in darkness. An indication of circumference is at the base. The sex toy is preferably manufactured from a flexible, durable material which is waterproof and easily cleaned. The markings are provided in alternating or contrasting color schemes, such as blue and yellow, or shapes such as triangles stacked on top of each other such that they may be easily read in reduced lighting conditions.