SELECT 
  cscart_products.* 
FROM 
  cscart_products 
WHERE 
  cscart_products.product_id IN (
    4896, 4889, 4894, 4891, 4895, 4890, 4892, 
    4893
  )

Query time 0.00027

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": 8,
      "filtered": 100,
      "index_condition": "cscart_products.product_id in (4896,4889,4894,4891,4895,4890,4892,4893)"
    }
  }
}