SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    9809, 9810, 9811, 9812, 9807, 9808, 10455, 
    10456, 10454, 10453, 10452, 10451, 
    10450, 10449, 10448, 10447, 12691, 
    12692, 12693, 12694
  )

Query time 0.00061

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_products",
      "access_type": "range",
      "possible_keys": ["PRIMARY"],
      "key": "PRIMARY",
      "key_length": "3",
      "used_key_parts": ["product_id"],
      "rows": 20,
      "filtered": 100,
      "index_condition": "cscart_products.product_id in (9809,9810,9811,9812,9807,9808,10455,10456,10454,10453,10452,10451,10450,10449,10448,10447,12691,12692,12693,12694)"
    }
  }
}