SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    1045, 1046, 1047, 1048, 1049, 1050, 1051, 
    1052, 1053, 1054, 1055, 1056
  )

Query time 0.00090

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 (1045,1046,1047,1048,1049,1050,1051,1052,1053,1054,1055,1056)"
    }
  }
}