Required when attaching 9523.61, 9523.62, 9523.63, or 9523.64 trays to Ikelite housings serial no. 37100 or less with male threaded mounting hardware (see photo) require the 9523.09 tray spacer, sold separately. Housings with female threaded mounting hardware do not require a separate spacer.
The MSRP referenced is a suggested US market retail price. Actual sales prices are set exclusively by Authorized Ikelite Dealers.