Golden Mountain sauce is composed mainly of fermented soybeans and salt. It tastes quite different from soy sauce, however—it is slightly saltier, plus there is a hint of sweetness since it contains sugar. There is no monosodium glutamate (MSG) in this sauce, but there is a small amount of "flavor enhancer"  which is similar to MSG, but without the negative effects.  This sauce has a similar flavor to Maggi seasoning sauce from Europe and is interchangeable.  It is a secret to many of Thai dishes.  
 
Product of Thailand