SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    1721, 1722, 1723, 1724, 1725, 1726, 1727, 
    1728, 1729, 1679, 1675, 1686
  )

Query time 0.00079

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 (1721,1722,1723,1724,1725,1726,1727,1728,1729,1679,1675,1686)"
    }
  }
}