SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    4725, 4735, 4024, 4020, 4028, 4037, 4019, 
    4029, 4036, 4742, 4744, 4743, 4741, 
    4904, 4502, 4501, 4504, 4503
  )

Query time 0.00040

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": 18,
      "filtered": 100,
      "index_condition": "cscart_products.product_id in (4725,4735,4024,4020,4028,4037,4019,4029,4036,4742,4744,4743,4741,4904,4502,4501,4504,4503)"
    }
  }
}