Product description: Aquarium co2 Pressure reducing valve Brand Name: ZRDR Model Number: R101/R102/R105/R101S/R102S/R105S Product Advantages 1. With precise pressure release valve (low pressure), More simply using 2. Accurate fine-tuning (regulate to 1 bubble/2-3 sec) 3. The bubble gauge with inverse valve. (regulation can be seen) 4.High purity aluminium regulator body, long-lasting durability and dependability 5.Dual gauge pressure indicators (tank volume and flow pressure / working pressure) 6.The bubble counter with advanced filtration and check valve to protect internal components of regulator Products in common: 1. The output pressure of R101, R102, and R105 is 0.3-0.4mpa. 2. Materials of R101, R102and R105 are installed and used in the same way. Product Differences: 1.R101 shows only the pressure inside the bottle for the mini single pressure gauge. R102 is a mini dual pressure gauge that can display the pressure inside the bottle or the output pressure. 3. R105 is a mini single pressure gauge with double output gas. 4. The difference between R101/R102/R105 and R101S/R101S/R105S is that the outlet direction of R101/R102/R105 spool valve cannot be adjusted, while the outlet direction of R101S/R102S/R105S spool valve can be adjusted in a universal way. Co2 Equipment pricelist website:http://www.wanyinsz.com/co2-equipment/