Hi guys- new subscriber here. Been playing for 40 years and started collecting in the last 10 years. I recently acquired a Slingerland Lo-boy. It is the Roy Duncan model and I saw it in a catalog from the mid to late 30's. It is complete with unstamped 10" cymbals. Does anyone have any more information on these? For example when were they first made and for how long were they produced? What famous players may have used them in their sets in the 30's and 40's? Are there any pictures with artists using this type of instrument? Just anything to help in my curiosity about this precursor to the Hi-hat! Thanks guys- I have other vintage stuff I will ask about as I get used to the site. I appreciate any information or direction to gain it!