SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    12500, 10200, 10201, 10566, 10545, 10227, 
    10552, 12506, 10693, 12508, 9953, 12522, 
    12507, 12498, 13101, 13100
  )

Query time 0.00082

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": 16,
      "filtered": 100,
      "index_condition": "cscart_products.product_id in (12500,10200,10201,10566,10545,10227,10552,12506,10693,12508,9953,12522,12507,12498,13101,13100)"
    }
  }
}