SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    18508, 18509, 18510, 18511, 18513, 18514, 
    18515, 18516, 18517, 18518, 18519
  )

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost": 0.01991781,
    "nested_loop": [
      {
        "table": {
          "table_name": "cscart_products",
          "access_type": "range",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "3",
          "used_key_parts": ["product_id"],
          "loops": 1,
          "rows": 11,
          "cost": 0.01991781,
          "filtered": 100,
          "attached_condition": "cscart_products.product_id in (18508,18509,18510,18511,18513,18514,18515,18516,18517,18518,18519)"
        }
      }
    ]
  }
}