Replacement Battery 1700mAh/6.29Wh Rechargeable Battery for Philips Pronto TSU-9400

here is my beloved Casio watch its model number is MQ - 30 W it's so old I need a battery for it it's so old Casio came out with this watch in 1992 it's still in fairly good condition not too many scratches on it now when I remove the back and remove this this is a stainless steel spring clip that wraps around the watch I found no battery inside so in this video I'll show you what you can do when you need a battery and you have nothing to go off on okay no manual no we used or spent battery nothing is available so what you need to do is of course measure and research I'll walk you through this thing here because you need the exact battery so of course this works if you have a calculator or any other small electronics item that you need a battery for you need to measure two things one is diameter so I'm gonna get closer with this vernier calliper this is a digital one and it's gonna show