SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    10516, 10517, 10518, 10519, 10520, 10521, 
    10641, 10640, 10639, 10638, 10637, 
    10636, 10635, 10634, 10633, 10632, 
    10631, 10630, 10629, 10628
  )

Query time 0.00050

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": 20,
      "filtered": 100,
      "index_condition": "cscart_products.product_id in (10516,10517,10518,10519,10520,10521,10641,10640,10639,10638,10637,10636,10635,10634,10633,10632,10631,10630,10629,10628)"
    }
  }
}