Buy Speed Control Motor

Buy offer Details

I have an interst on 7IDG2-6G for my small hoby.
What is the difference between 7IDG2-6G and 7IDS2-6G.
It is reversable motor, so I want to know how frequently it is reversing the rotating direction.
And how I can control the direction in how long period of time.
How much do I need to pay for a couple of products.
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I look forward to receiving your call.
Thank you in advance.