1、Suitable for closed arowana fish tank and open water plant tank. 2、Great for koi fish, goldfish, parrot fish, arhat fish, arowana, tropical fish, benthic fish, etc. 3、Available for granular fish food, large grain fish food, granular fish food, thin fish food, strip fish food. 4、Can automatically feed fish food, two different capacity feeding box, meet you different needs. 5、With different mode to be adjusted, convenient to control fish food intake. Features: 1.Suitable for closed arowana fish tank and open water plant tank. 2.Great for koi fish, goldfish, parrot fish, arhat fish, arowana, tropical fish, benthic fish, etc. 3.Available for granular fish food, large grain fish food, granular fish food, thin fish food, strip fish food. 4.Can automatically feed fish food, two different capacity feeding box, meet you different needs. 5.With different mode to be adjusted, convenient to control fish food intake. Specifications: Material: ABS Color: As picture shown Size: Approx. 12x8x14cm/ 4.7x 3.1x 5.5in Feeding box capacity: 50g/100g Can be clamped of fish tank thickness: Approx. ≤17mm Options: AK-01S, AK-02 AK-01S: 2 work modes to be freely adjusted: 12/24 hours Power supply: 2 x AA battery (not included) AK-02: 3 work modes to be freely adjusted: 8/12/24 hours Power supply: 2 x AA battery (not included); USB , USB cable power is 5V/1A. Note: When the 5V power supply suddenly black out, it will automatically switch to battery power mode. Note: When installing, please adjust the switch to the minimum to prevent the feed from leaking out. Two fixed ways Easy to use: base funnel, retaining clip Base funnel fixed: suitable for covered fish tanks. First attach the side of the hoop and loop to the bottom of the base funnel, then attach the other side to the fish tank cover, align the base funnel hole with the reserved hole of the fish tank cover, and fix it with the hook and loop. Fixed clip fixing: suitable for open fish tanks. Install the feeder holder into the main body of the feeder, place it in the horizontal direction of the edge of the aquarium, and tighten the clip of the clip. Packing List: AK-01S: 1 x Feeder 1 x Fixing clip 1 x Base Funnel 1 x Big Feeding box 1 x Small Feeding box 1 Set  x Hook&loop(2 pcs) AK-02: 1 x Feeder 1 x Fixing clip 1 x Base Funnel 1 x Big Feeding box 1 x Small Feeding box 1 x USB cable 1 Set x Hook&loop(2 pcs) It will according your choose. Notices For Use: 1. About the battery: Since the battery cannot be mailed, the buyer needs to bring his own battery. Continuing for 3-6 months depending on the number of meals. 2. About feeding food: The feeding device can be set to feed once every 8 hours, once every 12 hours, and once every 24 hours. Small feed bin 50g, large feed bin 100g. Instructions for use: 1. Open the battery compartment and insert the battery (without battery) 2. Pull out the feed bin in the direction of the arrows and add the feed. 3. Adjust the size of the spout as needed. 4. Different interval feeding modes, respectively, relative to the automatic feeding time, the timing is selected after the mode is selected.(Note, do not fall into the water).