SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    1735, 2166, 756, 1870, 2009, 2016, 2236, 
    2308, 2326, 2384, 585, 851
  )

Query time 0.00101

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 (1735,2166,756,1870,2009,2016,2236,2308,2326,2384,585,851)"
    }
  }
}