SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    12508, 12506, 12500, 12499, 12513, 12514, 
    13099, 12521, 12527, 12511, 12512, 
    12528, 12520, 12497, 12505, 12502, 
    12504, 10847, 13152, 10846
  )

Query time 0.00095

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 (12508,12506,12500,12499,12513,12514,13099,12521,12527,12511,12512,12528,12520,12497,12505,12502,12504,10847,13152,10846)"
    }
  }
}