Flash with a guide number of 20, compatible with ISO 100-400, for 28mm lenses. - Brand: National - Model: PE-220S - ISO Sensitivity: 100, 200, 400 - Guide Number: 20, 28, 40 - Usable Focal Length: 28mm - Angle Adjustment: 0°, 45°, 75°, 90° Thank you for viewing. Untested, sold as is. Only a simple wipe-down has been done. The condition is as shown in the photos. Please consider the photos and the above information before bidding. Please refrain from bidding if you are overly concerned about details. Cancellations and returns/refunds are not accepted after a bid has been placed. Please understand that this is a used item, and there may be some scratches, dirt, and signs of use. Please check the images for detailed information. Please understand that no claims or returns are accepted after winning the auction.