SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    10566, 10567, 10568, 10569, 10572, 10573, 
    10575, 10576, 10577, 10578, 10579, 
    10580, 10581, 10582, 10583, 15944, 
    15945, 15946, 15947, 15949
  )

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": 20,
      "filtered": 100,
      "index_condition": "cscart_products.product_id in (10566,10567,10568,10569,10572,10573,10575,10576,10577,10578,10579,10580,10581,10582,10583,15944,15945,15946,15947,15949)"
    }
  }
}