Virtually all of the major bedding manufacturers have either gone totally to that design, abandoning the two-sided design, or have allotted a healthy percentage of their products to it. mattress construction appears to be a one-sided issue
Bird Spider and Bird Eating Spiders. The Chinese bird spiders are venomous spiders capable of delivering a rather dangerous bite. Their LD50-value is low and in the same range as many loxosceles species (brown recluse spiders). Chinese bird spiders are tarantulas, just like the goliath bird eating spider is a tarantula. Chinese bird spiders are widely distributed in Asia and are abundant in Southern China.
Although most of the 35,000 species of spiders eat insects, some have a more diverse diet. Most spiders will not hesitate to cannibalize one another. All spiders prefer live food and large species like tarantulas are powerful enough to take on small birds, lizards, frogs and millipedes.