SELECT 
  product_id 
FROM 
  cscart_mb_ali_products 
WHERE 
  product_id IN (
    20525, 20526, 20527, 20528, 20529, 20530, 
    20531, 20532, 20533, 20534, 20535, 
    20536, 20537, 20538, 20539, 20540
  )

Query time 0.00012

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "table_name": "cscart_mb_ali_products",
      "access_type": "range",
      "possible_keys": ["product_id"],
      "key": "product_id",
      "key_length": "4",
      "used_key_parts": ["product_id"],
      "rows": 16,
      "filtered": 100,
      "attached_condition": "cscart_mb_ali_products.product_id in (20525,20526,20527,20528,20529,20530,20531,20532,20533,20534,20535,20536,20537,20538,20539,20540)",
      "using_index": true
    }
  }
}