SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    283, 1247, 1110, 985, 1300, 1035, 1028, 
    603, 1268, 1269, 1392, 1380
  )

Query time 0.00083

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 (283,1247,1110,985,1300,1035,1028,603,1268,1269,1392,1380)"
    }
  }
}