SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    2400, 2403, 2413, 772, 781, 1635, 1660, 
    1688, 1764, 1869, 1907, 2313
  )

Query time 0.00081

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 (2400,2403,2413,772,781,1635,1660,1688,1764,1869,1907,2313)"
    }
  }
}