SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    10699, 10695, 10195, 10576, 10696, 9760, 
    10583, 10701, 10582, 10139, 12503, 
    10575, 9932, 10075, 10135, 9952
  )

Query time 0.00053

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": 16,
      "filtered": 100,
      "index_condition": "cscart_products.product_id in (10699,10695,10195,10576,10696,9760,10583,10701,10582,10139,12503,10575,9932,10075,10135,9952)"
    }
  }
}