SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    317, 189, 501, 293, 78, 35, 234, 331, 484, 
    287, 292, 79
  )

Query time 0.00108

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": 12,
      "filtered": 100,
      "index_condition": "cscart_products.product_id in (317,189,501,293,78,35,234,331,484,287,292,79)"
    }
  }
}